Category: Class 9

AP State Syllabus AP Board 9th Class English Textbook Solutions Chapter 2B What is a Player? Textbook Questions and Answers.

AP State Syllabus 9th Class English Solutions Chapter 2B What is a Player?

9th Class English Chapter 2B What is a Player? Textbook Questions and Answers

I. Answer the following questions.

Question 1.
What are the qualities that a true player should have?
Answer:
A true player accepts defeat with ease. He learns from his failures. He loves to share and enjoys the rival’s victory too. He knows his abilities. He continuously works for progress. He practises in all seasons and at all times. He never complains. He is not worried about past failures. He thinks of the present and plans for the future.

Question 2.
What, according to the poet, is an unacceptable crime of a player?
Answer:
Complaining about play time is an unacceptable crime.

Question 3.
Which game do you like the most? What are the qualities of a player stated in the poem? Which of them do you have?
Answer:
I like volleyball the most. The poem lists the qualities of a player. They are accepting defeat, learningfrom failures, continuous practice, knowing one’s own limitations, sharing, not complaining, not worrying about past defeats, focussing on the present, and contributing to the game. I have some of them. They are : accepting defeat, regular practice, learningfrom failures, not complaining.

Question 4.
The poet talks about certain Do’s and Don’ts for a true player. List them out in the following table. One is done for you.

Answer:

What is a Player? Summary in English

Jessica Taylor’s poem, “What is a Player” lists the qualities a good player possesses. An ideal player continues despite defeat and learns from failures. A good player finds pleasure in sharing and enjoys the rival’s victory too. A true sportsman never complains about his chances, for he knows it is a crime. A model player practises regularly and keeps in mind that success is not always guaranteed. The real player always aims high, works for continuous advancement, and practises day and night; in rain and shine and when healthy or not. A player is always sensible and never worries about past defeats and thinks of the present and plans for the future. A true player doesn’t do something in fear and wants to contribute to the game as long as he is there.

What is a Player? Glossary

give up (phr.v) : quit, leave

buzzer(n) : bell

whine (v) : complain

hurt (adj) : injured

sensible (adj) : reasonable, logical, sane

pondering (v + ing) : thinking

contemplating (v) : thinking; planning

chicken out (phr. v) : to decide not to do something because of fear

counts (v) : be important

AP State Syllabus AP Board 9th Class Social Studies Important Questions Chapter 19 Expansion of Democracy.

AP State Syllabus 9th Class Social Studies Important Questions 19th Lesson Expansion of Democracy

9th Class Social 19th Lesson Expansion of Democracy 1 Mark Important Questions and Answers

Question 1.
The map below shows the democratic countries that existed between 1900 and 1950. (SA-II : 2018-19)

Answer:
Canada, Great Britain, U.S.A., Alaska, Peru, Chile, etc

Question 2.
Name the country which is marked by “A”. (SA-II : 2016-17)

Answer:
Russia.

9th Class Social 19th Lesson Expansion of Democracy 2 Marks Important Questions and Answers

Question 1.
Do you think our country has a liberal democratic political system? Give your reasons? (SA-II : 2016-17)
Answer:
Yes, our country has a liberal democratic political system by following methods.

1. Free and fair regular elections.
2. Written constitution.
3. Equality before law.
4. Universal Adult Franchise etc.

9th Class Social 19th Lesson Expansion of Democracy Important Questions and Answers

Question 1.
Compare the struggles for democracy in Libya and Burma on the following aspects
A) Leadership
B) Nature of struggle
C) Process of transition.
Answer:

Question 2.
Read the following information and answer the questions given below.
Events and year of occurrence

1) Which of the above two countries first became independent? And when did it happen?
Answer:
Burma was the first country to get independence. And she got it in 1948.

2) Who was the dictator that ruled over Libya?
Answer:
“Gaddafi” ruled over Libya.

3) Who was Aung San?
Answer:
Aung San was the leader of Nationalist movement in Burma.

4) Which of the two countries became democratic first?
Answer:
Burma in 2010.

5) Where are the two countries located?
Answer:
Libya is in Africa and Burma is in Asia.

Question 3.
What are “economic sanctions” ? How do they work on any country’s economy?
Answer:

• Economic sanctions are restrictions imposed on any country regarding imports and exports.
• Import of goods from that country will be banned.
• Export of goods to that country will be stopped.
• Due to that the country’s economy will generally be effected.

Question 4.
What are the steps taken by “the UNO” with regard to Libya or Burma?
Answer:

• The UNO intervened and supported rebels by declaring Libya to be a “No fly zone”.
• Later with the help of US, Britain and France it bombarded the government positions in Libya.
• As a result a new government was formed in on 14th Nov. 2012,
• “Economic Sanctions” were imposed to put pressure on rulers.
• An election was held under the observation of the UNO in 2010.

AP State Syllabus AP Board 9th Class English Textbook Solutions Chapter 2A True Height Textbook Questions and Answers.

AP State Syllabus 9th Class English Solutions Chapter 2A True Height

9th Class English Chapter 2A True Height Textbook Questions and Answers

Read the following quotation and answer the questions that follow.

Question 1.
What, according to you, does this quotation express?
Answer:
The quotation tells us to dream first, think about it next and work on it finally.

Question 2.
Is it essential to dream high? How can anyone make one’s dream come true?
Answer:
Yes, it is good to dream high. Our dear Teacher Dr. APJ Abdul Kalam rightly says, “small aim is a big crime”.

One can make one’s dream come true with careful planning and continuous, consistent work with confidence, competence and with dedication, and discipline.

Question 3.
What is your dream in life?
Answer:
My dream in life is to become a man-making teacher and work for quality human resource development.

Question 4.
Have you ever heard of a child with special needs becoming a champion?
Answer:
Yes, I have heard of a child with special needs becoming a champion. A sixteen year old child with multiple complaints completed the cycling race much ahead of hundreds of healthy and older participants

Comprehension

I. Answer the following questions.

Question 1.
What was Michael Stone’s dream?
Answer:
Michael Stone’s dream was to become a champion in pole-vaulting.

Question 2.
What impact did the mother’s stories have on Michael?
Answer:
Michael’s mother, Mildred Stone was a good story teller. When Michael was growing up, she told him a number of stories about flying. They were full of details and colour. They inspired Michael to dream high. In his dreams, he would outrun motorcars and fly like an eagle.

Question 3.
How did Michal prepare himself to become an Olympic champion?
Answer:
Even as a young boy of 14, Michael started working hard. He began a careful, disciplined weightlifting programme. On alternate days, he practised running. His father supervised his preparation. Michael always strived for perfection. Thus his preparation to become an Olympic champion was planned, complete and perfect.

Question 4.
Michael’s mother and father had different ideas about training. How did these two approaches help Michael fulfil his dream?
Answer:
Michael’s parents had different ideas about training. Mother encouraged the much needed dreaming. And father demanded the essential hard work. Mother provided inspiration. Father brought out perspiration (hard work). Thus Michael derived help from his parents.

Question 5.
What was so special about Michael’s achievement?
Answer:
Michael’s achievement was really so special. Michael was blind. And yet he became an Olympic champion.

Vocabulary

I. Synonyms :

Use a thesaurus/dictionary to find out synonyms of these words from the biographical account you have read.

Answer:

Note: Synonyms are words with similar not the same – meaning. Synonyms should belong to the same part of speech.

II. Suffixes :

Suffixes are groups of letters that are attached to words at their ends. (Groups of letters attached to words at their beginnings are called prefixes.) Suffixes generally change the parts of speech of the words to which they are attached.

Look at the following words taken from the passage.

Now, pick out the suffix from each word and form new words of your own in the table given below. One is done for you.

Answer:

III. Collocations :

A collocation is an arrangement of words or other elements, especially those that commonly cooccur.
e.g.: heart-felt congratulation.
There are certain word combinations.

• Adjective + Noun : e.g. bright/harsh/intense/strong light
• Verb + Noun : e.g. cast/ emit/give/provide/shed light
• Noun + Verb : e.g. light gleams/glows/shines
• Noun +Noun : e.g. a light source
• Preposition+ Noun : e.g. by the light of the moon
• Noun+ Preposition : e.g. the light from the window
• Quantifier+ Noun : e.g. (of) a beam / ray of light

Use a dictionary and write which word in column 1 can collocate with those in the next five columns. Put a tick (✓) mark in the relevant column. Use the apt collocations in your own sentences.

Answer:

Sentences using collocations :

1. The mother has heartfelt sympathy on her children.
2. I received heartfelt congratulations from my friends when I obtained good marks.
3. You have our deep sympathy on the loss of your father.
4. Becoming a police officer was my childhood dream.
5. He expresses his opinion on his marriage with Latha.
6. Expressing strong opinion on you is very difficult to me.
7. She received a warm welcome from her friends in America.

Grammar

Look at the following sentences taken from the reading passage:

1. As he raced down the golden-lined wheat fields, he would always outrun the locomotives passing by.
2. When he heard the singing of some distant robins in flight, he knew it was his time to fly.
3. Since the other vaulter had fewer misses, Michael needed to clear this vault to win.

In the above sentences the clauses with as and when denote time whereas since denotes reason. As and when refer to time and the other parts state what happened at that time. In the third sentence, the clause beginning with since states the reason and the other states the consequence.

The words as, when, since are conjunctions, which connect two sentences (clauses). The clauses containing these words are called Adverbial clauses. These adverbial clauses cannot stand independently, so they are called Dependent clauses orSubordinate clauses. The clause that stands on its own is an Independent clause or Main clause.

The linkersas, when and since (Adverbs) are placed before the clauses to make them Subordinate clauses.

Now, read the biographical account once again and pick out the Adverbial clauses and Main clauses and write them in the table or in your notebook.

Answer:

Complete the following sentences with appropriate Adverbial clauses. Use the adverbs wherever they are given in brackets.

1. The teacher entered the class ___________ .
2. The dog ran into a speeding car ___________ .
3.1 was in deep sleep ___________ .
4. Someone knocked at the door ___________ .
5. The crowd cheered Michael Stone ___________ . (as soon as)
6. It is high time the cricket board thought of different alternatives ___________ . (as)
Answer:

1. The teacher entered the class when the bell had rung.
2. The dog ran into a speeding car as it did not notice the car.
3. I was in deep sleep when father came home and tried to wake me up.
4. Someone knocked at the door as I was doing my homework.
5. The crowd cheered Michael Stone as soon as he cleared the 17 feet 6½ inches height.
6. It is high time the cricket board thought of different alternatives as there have been a series of failures on the part of the Indian cricket team.

Writing

You have read the biography of Michael Stone. Think of some world-famous sporting personalities from India. Collect information about any one of them and write a biographical sketch.
You may include the following:
1. Date and place of birth
2. Information about the family
3. Achievements of the person : awards, prizes, honors, etc.
4. Important events in the life of the person – education, marriage, profession, etc.
5. Inspiration to others/message to the society
6. Contribution to his/her field and society
Answer:
Abhinav Bindre – The Ace Shooter

India’s thirst for a gold in Olympics individual events remained unquenched for over a hundred years. India had a taste of the individual gold only in 2008 Beijing Olympics when Abhinav Bindre achieved the land mark in 10M Air Rifle Shooting.

Abhinav Singh Bindre was born on 28 September 1982 in Dehradun in Uttarakhand (then Uttar Pradesh). Born into a very wealthy family of Sikhs, he had his early education in the world famous Doon School. Later, he moved to St. Stephen’s School from where he graduated in 2000. He did his B.B.A. in Colorado University of the U.S.A. He did a Diploma course in Mental Management too. He was pursuing his Doctorate in Business Management.

His skill as an expert shooter was identified quite early. His very supportive and affluent parents had got built exclusively for Bindre an indoor shooting range at home in Patiala! Services of a Mental coach Surabh Bhattacharjee, Lt. Col. Dhillon, and five time Olympic shooter Gabriele Buhlmans were made available to young Bhindre.

With his innate skills and excellent support from family, Bhindre started to shine from a very young age. At 15, he was the youngest participant in 1998 Commonwealth Games. His successes since then have been continuous and remarkable. He won a Bronze medal in the 2001 Munich World Cup. But in the same year, he won six Gold medals in various international events. 2002 Manchester Commonwealth Games crowned him with another Gold. 2004 Olympics saw him break the previous records, though he failed to win a medal. And in 2006, he became the first Indian to win the World Championship. 2006 Melbourne Commonwealth Games added one more Gold to his tally. Severe backache didn’t deter him from winning an Olympic Gold in 2008.

Various State Governments and Central Government honoured him amply and rewarded him with cash prizes. Arjuna Award in 2000 and Rajiv Gandhi Khel Ratna in 2001 are remarkable honours for him. Most memorable for him must be his flag bearing role in the opening ceremony of 2010 Commonwealth Games and taking the Athlete’s oath on behalf of 6,700 participants from 71 countries.

A Shot at History – My Obsessive journey to Gold is his version of his achievements. Abhinav Bindre’s life and achievements remain a source of inspiration to young aspirants.

Study Skills

You have finished reading the text “True Height”. Write the summary of the story in your own words. Use the following ideas to complete your summary effectively.

• Make a note of the important points in the text and the supporting details.
• Sequence of the events.
• Identify the words/ phrases which carry ideas.
• Use appropriate linkers.
• Focus on the words/phrases that express the essence of the text.
• Present the ideas briefly in your own words.
• Do not include examples in the summary.

Summary of The Reading Text

“True Height’ is a truly touching story of Michael Stone, written by David Naster. Michael was the son of Bert and Mildred Stones. Mildred always told Michael stories of flying high. That made Michael dream and dream high. Father Bert was a practical man. He always wanted Michael to work hard to win. He was also a coach and trainer to his son. With inspiration from mother, guidance from father, and his own determination, dedication, and discipline, Michael grew into an excellent pole-vault expert with the flexibility of an athlete and the strength of a body builder. Michael was also a good student and helped parents in their farm work. With his regular practice, devoted work he went on reaching unbeatable heights in pole-vault. By clearing 17 feet 6½ inches Michael created National and International Junior Olympics record. Congratulations overwhelmed Michael. Father was crying the greatest tears of pride. Michael Stone’s success was very significant. The reason … Michael Stone was blind.

Listening

Practise listening carefully. Then you will be able to speak.
Listen to the commentary on a cricket match and answer the questions.

Cricket Commentary

Hello, good morning, viewers. This is Sunil Gavaskar with Ravi Sastry. Welcome to Uppal Cricket Stadium, Hyderabad. It is a sunny morning. Electrifying atmosphere in this jam-packed Stadium. The crowd is expecting an exciting match-a war of nerves between the arch rivals, India and Pakistan. The local boy V.V.S. Laxman is the centre of attraction as it is his home ground.

Having won the toss, India elected to bat first. The inform openers Gambhir and Sehwag are at the crease.

The first ball of the day, an in-swinging yorker into the pads of Sehwag from Umar Gul. He is all hands up. There is a loud appeal for Ibw. Luckily, for Sehwag and for India it is a noball. There is absolute silence in the stadium.

Here comes Gul again! Sehwag is ready. Gul pitches the ball at the good length area. Sehwag goes backfoot, plays it gently to the square leg area. The batsmen cross for a quick single. Sehwag opens his account with that single. India is 2 for no loss of a wicket.

This brings Gambhir on to strike. The third ball of the over. This time a slightly misdirected ball on the leg stump and Gambhir comes forward and hits straight over the head of the bowler for a four.

Gul changes the guard. This time a very well-directed short-pitch delivery. Oh! What a delivery. But Gambhir connects the ball. What a sweet timing! In a flash the ball disappears into the stands. The umpire Steve Buckner declared it a six. The crowd jump on to their feet. With that Gambhir quickly moves on to 10 and India 12 without loss. There is a conversation between Gul and Shahid Afridi. It seems the captain has a piece of advice. And there is some field adjustment for Gambhir, Now let’s see how it works.

Umar Gul comes in and bowls to Gambhir. What a cracking delivery! It breaks the defense of Gambhir, Oh! The middle stump goes cart-wheeling. He’s out. Pakistan celebrates. The jubilant Gul runs to hug his captain. The crowd is dumbstruck. But the umpire Buckner signalled it a noball. Gambhir survives. A great sigh of relief on his face. How lucky this man is! The crowd comes alive again and cheers up. What an excitement in the very first over itself!

The final ball of the over. This time it is a slow ball from Gul. Gambhir elegantly pushes the ball to the onside and completes the run but there is a fumble by the fielder. The batsmen try for the second. Will they complete it? Yes. Now the score moves on to 15. Gambhir is on 12.

I. Tick (✓) only the correct ones from the statements given below.

1. Sachin and Gambhir opened the Indian innings. (✗)
2. Umar Gul opened the Pakistan’s attack. (✓)
3. Laxman is one among the Indian squad. (✓)
4. Gul bowled out Gambhir. (✗)
5. India is 15 without loss after the first over, (✓)

II. Answer the following questions.

1. Which two world teams of cricket do you like? Why?
Answer:
I like Indian team and Australian team, I love their art of playing, team spirit, sporting spirit and human approach.

2. Who are the openers?
Answer:
Sehwag and Gambhir are the openers.

3. Who are the commentators?
Answer:
Sunil Gavaskar and Ravi Sastri are the commentators.

III. Complete the Score Board given below.
India Vs Pakistan

Answer:

Oral Activity

Imagine, you were listening to the commentary, your father came there and reminded you of the ensuing examinations. He said, “Listening to cricket commentary is a waste of time.” Now develop a conversation between you and your father.
Answer:
Father : Hey Avinash ! What are you doing ? Examinations are just a week ahead, and you are listening to cricket commentary ! Isn’t it a sheer waste of time ?

Avinash : Sorry father! I just started to listen to commentary. I have been studying lessons for long. As I felt like relaxing for a few moments, I switched on the radio.

Father : But you can listen to music to ralax.

Avinash : True, father. But cricket commentary can also be useful in many ways. First, it gives us a chance to improve listening skills. Then it gives us quite interesting information. Analytical and presentation skills can also be improved. Sometimes we feel inspired to achieve great goals too I

Father : Sounds you are right. But I have my own doubts.

Avinash : Your doubts have base father. If we become an addict to commentary, we will waste all our time. As long as we are within our limits, listening to cricket commentary can be a productive and enjoyable activity.

Father : Seems we elders can pick up a point or two from you brilliant boys I

Avinash : Oh father, thanks a lot. But I will be in my limits.

Father : Good, son ! Continue to progress and prosper!

Avinash : I will try my level best father!

True Height Summary in English

“True Height’ is a truly touching story of Michael Stone, written by David Naster. Michael was the son of Bert and Mildred Stones. Mildred always told Michael stories of flying high. That made Michael dream and dream high. Father Bert was a practical man. He always wanted Michael to work hard to win. He was also a coach and trainer to his son. With inspiration from mother, guidance from father and his own determination, dedication and discipline, Michael grew into an excellent pole-vault expert with the flexibility of an athlete and the strength of a body builder. Michael was also a good student and helped parents in their farm work. With his regular practice, devoted work he went on reaching unbeatable heights in pole-vault. By clearing 17 feet 6^ inches Michael created National and International junior Olympics record. Congratulations overwhelmed Michael. Father was crying the greatest tears of pride. Michael Stone’s success was very significant. The reason … Michael Stone was blind.

True Height Glossary

height (n) : an extreme example of a particular quality
Note : Be careful about the spelling. It is h-e-i-g-h-t; not ‘high (adj) +1.’ And the letters ‘gh’ are silent.

athlete (n) : a person competing in sports

pursue (v-pre tense) : try to achieve

nerve-wracking (adj) : exciting; making one tense

ultimate (adj) : final, last, best

career(n) : job or work in a particular area

awe-inspiring (adj) : impressive; admiring

breathless (adj) : making one react emotionally

quenched (v-past tense) : satisfied

intensity (n) : a great extent; depth

astroturf (n) : artificial grass surface used in sports

confronted (v-past tense) : faced

pole vault (n) : a game in which a person jumps high with the help of a pole (a long stick)

gymnast (n) : a person participating in activities/sports that need strength and flexibility

fantasy (n) : a pleasant situation only in imagination

quest (n) : a long search

bird’s eye view (idiom) : a view from a high position

recurring (v-ing) : happening again and again

soaring (v-ing) : going up and up

coincide (v) : happen to be the same

hard-core (adj) : unchanging, firm in belief, strong

regimented (adj) : strictly disciplined

coach (n) : a person who guides, teaches techniques of a game

chores (n-plural) : works done regularly

persistence (n) : continuing to do something despite difficulties

obsession (n) : a state in which a person’s mind is completely filled with a thought of one particular thing/person.

arrogant (adj) : proud

inflated (adj) : filled with air

oblivious (adj) : not aware of; forgotten

surpassed (v – past tense) : exceeded; crossed

ritual (n) : a customary practice; formality

startled (v-past tense) : surprised; confused; threatened

bale of hay (n. phrase) : a bundle of dry grass

accurate (adj) : exact

envisioned (v-past) : saw in imagination

scared (adj) : afraid

a trickle (n) : drops in a series

pounding (v-ing) : beating quickly and noisily

The silence was deafening : The silence was unbearable
(Note the speciality of the expression – a paradox)

sprinting (v-ing) : running fast

eruption (n) : sudden, strong expression of powerful feelings by shouting

swarmed with (phrase) : surrounded by

accomplishment (n) : achievement

AP State Syllabus AP Board 9th Class Social Studies Important Questions Chapter 14 Democratic and Nationalist Revolutions 19th Century.

AP State Syllabus 9th Class Social Studies Important Questions 14th Lesson Democratic and Nationalist Revolutions 17th and 18th Centuries

9th Class Social 14th Lesson Democratic and Nationalist Revolutions 19th Century 1 Mark Important Questions and Answers

Question 1.
How do you appreciate the Cavours role in unification of Italy? (SA-II : 2017-18)
Answer:
Cavour’s work in the Unification of Italy is appreciable.
He unify the regions of Italy through a tactful diplomatic alliance with France and he worked neither a revolutionary nor a democrat.

Question 2.
Who formed ‘Young Italy’? Why? (SA-I : 2019-20)
Answer:
Young Italy was formed by Joseph Mazzini.
The main reason is to unified Italy and would touch off a European wide revolutionary movement.

9th Class Social 14th Lesson Democratic and Nationalist Revolutions 19th Century 2 Marks Important Questions and Answers

Question 1.

Read the map given above and answer the following questions. (SA-III : 2016-17)
1. Mention the names of any two islands that are shown in the map?
2. The states which are shown above, are parts of which country now?
Answer:
1. Corsica, Sardinia, and Sicily.
2. At present the states which are shown in map are related to the country Italy.

Question 2.
What were the political, social, and economic ideas supported by the liberals in France in the beginning of 19th century? (SA-I : 2018-19)
Answer:
Political, social, and economic ideas supported by liberals.
→ Freedom for the individual.
→ Equality of all before the law.
→ Concept of government by consent.
→ End of autocracy and privileges of the church.
→ Constitution and representative government through parliament.
→ Inviolability of private property.

Question 3.
With reference to the Unification of Germany, answer the following questions. (SA-I : 2019-20)
i) Which country took leadership for Unification of Germany?
Answer:
Prussia.

ii) With what 3 countries did Bismarck go to war to achieve German unification?
Answer:
Denmark, Austria, and France.

9th Class Social 14th Lesson Democratic and Nationalist Revolutions 19th Century 4 Marks Important Questions and Answers

Question 1.
The French women fought for which rights ? in the context of India, were the women given all these rights? Write your analysis. (SA-I : 2018-19)
Answer:
French women fought for Right to vote, Right ot contest to Legislature, and Right to capture political power.
Then in the context of India all Indian women who are eligible, get all the above rights. Even though in the issue of gaining above the rights some negligence is there in India.

1. Representation of women in legislature is very less.
2. Women Reservation bill is still not approved in Lok Sabha.
3. Very less women are in political posts.

Question 2.
Describe the process of Italian Unification in 19th Century. (SA-II : 2018-19)
Answer:
Unification of Italy :
I Stage :
In 1830s Guiseppe Mazzini had sought to put together a coherent programme for a Unitary Italian Republic.
He had also formed a secret society called Young Italy for the dissemination of his goals.

II Stage :

• Prime Minister Cavour who led the movement to unify the regions of Italy, was neither a revolutionary nor a democrat.
• Through a tactful diplomatic alliance with France, he defeated Austria.

III Stage :

• Under the leadership of Garibaldi, a large number of Red Shirts army joined the fray.
• In 1860 they marched into South Italy and the kingdom of the Two Sicilies and succeeded in winning the support of the local peasants in order to drive out the Spanish rulers.

IV Stage :
Finally, Victor Emmanel II occupied Rome, and Unification of Italy completed. In 1871 Victor Emmanuel II was proclaimed king of unified Italy.

9th Class Social 14th Lesson Democratic and Nationalist Revolutions 19th Century Important Questions and Answers

Question 1.
Write about Jacobins constitution.
Answer:

• Under the Jacobian constitution, all people were given the right to vote and the right to insurrection.
• The constitution stated that the Government must provide the people with work or livelihood.
• The happiness of all was proclaimed as the aim of government.
• The government abolished slavery.
• Hence the Jacobians was the first genuinely democratic constitution in history.

Question 2.
How did nationalism and the idea of the nation-state emerge?
Answer:

• A nation state was one in which the majority of its citizens came to develop a sense of common identity and shared common history.
• This commonness did not exist from time immemorial, it was forged through struggles, through the actions of leaders and the common man.
• The French revolution gave the term “nation” its modern meaning.
• A nation is not the territory but the people who make it.
• The French revolution gave the meaning of sovereignty that the people constituting the nation are the source of all power and authority.
• Government is answerable to its people.

All these ideals led to the formation of the nation-states.

Question 3.
Discuss the importance of language and popular traditions in the creation of national identity.
Answer:

• Language and popular traditions are important in the creation of national identity.
• National identity means people feeling that they belong to a nation irrespective of their caste, religion, colour, etc.
• The language makes people identify themselves as a one race or a nation.
• Also, the popular traditions such as Roman culture and tradition etc. easily attracted the people and strengthened the national integrity.

Question 4.
In what ways do you think could the French revolutionaries help the other people of Europe to become nations?
Answer:

• I think the French revolutionaries could help the other people of Europe to become nations.
• The French revolutionaries fought for the principles of liberty, equality, and fraternity.
• They proved that France was not just a territory but the French people.
• The revolutionaries further declared that it was the mission and the destiny of the French nation to liberate the peoples of Europe from despotism, in other words, to help other people of Europe to become nations.

Question 5.
Do you think the anti-Nizam movement was a nationalist movement like French revolution? Compare the similarities and differences between the two movements.
Answer:

• Anti-Nizam movement was a nationalist movement like French Revolution.
• Both these were against the rulers at that time.
• The revolutionaries in French revolution became violent at times, whereas the activists in anti-Nizam movements suffered a lot in the hands of Nizam army.

Question 6.
Why do you think liberal democracy was reluctant to give right to vote to women and propertyless men?
Answer:

• Liberals did not ensure universal right to vote for all the people.
• Right to vote and get elected was given only to property – owing men.
• Men without property and all the women were not given any political rights.

Question 7.
In what ways were the liberals different from the conservative monarchists and how were they different from the radical poor?
Answer:

• Liberals believe that government should work by consent of people.
• Liberals believe people should have equal freedom and all are equal before law.
• Constitutional Monarchists believe in privilege of rich landlords and powers of monarch.
• They want to use modernization as a tool to increase control over the state.
• Radical poor wanted to bring change in the order with a reign of terror.

Question 8.
Why do you think were defeated by the conservatives?
Answer:

• Liberals talked of political democracy only and no equality was propogated.
• They did not even supported universal franchise and equality before law.
• But conservatives used modernization to have greater control overstate.
• They wanted to abolish serfdom and federalism and installation of modern army, dynamic economy, etc.

Question 9.
Read the following passage and answer the questions given below.

1) What was the first genuinely framed constitution in the world?
Answer:
Jacobin’s constitution was the first genuinely framed constitution in the world.

2) Why was the Jaccobians constituion called the first genuinely framed constitution?
Answer:
1) The Jacobin’s constitution gave the right to vote to all citizens.
2) The constitution stated that the government must provide the people with work. Hence it was called the first genuinely framed constitution in the world.

3) Who was the dictator that ruled over France during early 19th century?
Answer:
Napoleon.

4) When were the revolutions occurred in France in the early 19th century?
Answer:
In 1830 and 1848, the France experienced revolutions.

5) When was the Republic proclaimed in france?
Answer:
The Republic was proclaimed in France in 1871 A.D.

Question 10.
Read the following passage and answer the questions given below.

1) Name the Alpine regions is the Habsburg Empire.
Answer:
The Tyrol, Austria and the Sudetenland, and Bohemia were the Alpine region.

2) In which language did the aristocracy speak in the Alphine region?
Answer:
The Aristocracy in the Alphine spoke in German.

3) What were the Italian speaking provinces of the Habsburg Empire?
Answer:
Lombardy and Venetia were Italian provinces.

4) A mass of subject peasant people lived in the empire. Name them.
Answer:
Bohemians, Slovaks, Slovens, Croats, and Roumans were peasant people that lived in the empire.

Question 11.
Why do you think conservatism needs to curb freedom to express one’s opinion and criticise?
Answer:

• Conservatism is the dominance of society by an aristocracy. It is incompatible with democracy, prosperity, and civilization in general.
• The conservatives did not tolerate criticism and dissent and sought to curb activities that questioned the legitimacy of autocratic governments.
• They imposed censorship laws to control the ideas of liberty and freedom associated with the French Revolution.

Question 12.
Read the following information and answer the questions given below.

a) What are the demand of middle classes? (SA-III : 2016-17)
Answer:
The demands of middle classes were

1. Constitution and
2. Representative government.

b) With the invasion on which country, did Napoleanic wars begin? (SA-III : 2016-17)
Answer:
Nepoleonic wars begin with invasion of Italy.

c) In which year was the Vienna peace conference held? (SA-I : 2018-19)
Answer:
Vienna Peace Conference was held in 1815 A.D.

d) Who was ruling France during the 1848 revolution? (SA-I : 2018-19)
Answer:
Louis Phillippe.

e) Who completed the unification of Italy? (SA-I : 2018-19)
Answer:
Victor Immanuel-ll, completed the Unification of Italy.

f) The Greek struggle for independence started in which year? (SA-I : 2018-19)
Answer:
1821 A.D.

g) When did Napoleon invade Italy?
Answer:
Napoleon invaded Italy in 1797 AD.

h) When was the Vienna Peace Settlement signed?
Answer:
The Vienna Peace Settlement was signed in 1815 A.D.

i) What were the two nations that united in the mid 19th centuries?
Answer:
Italy and Germany were the two nations that united in the mid 19th century.

j) Who revolted against economic hardship?
Answer:
Industrial workers and peasants revolted against economic hardship.

k) What were the demands of the middle class in 1848 revolt?
Answer:
The middle class demanded constitutions and representative governments.

Question 13.
Do you think our country has a liberal democratic political system? Give your reasons.
Answer:

• In India supreme power rests with the people.
• India is a republic country.
• Everyone is equal before law.
• Every citizen of 18 years and above has the right to vote.
• Any citizen is eligible to contest for any political office.

Hence we can say India has liberal democratic political system.

Question 14.
Point out the following on the Europe map.

1. Corsica
2. Sardinia
3. Poland
4. Germany
5. France

Question 15.
Locate the following on the Europe map.

1. Hungary
2. Serbia
3. London

Question 16.
What is the caricature? What does it represent?
Answer:

• A funny drawing of someone that makes them look silly or sometimes criticizes someone.
• It usually tells us about an incident or a person of that age.
• It symbolizes the wrong practices or criticizes that person on that grounds or informs us about the other side of that person.

AP State Syllabus AP Board 9th Class English Textbook Solutions Chapter 1C Little Bobby Textbook Questions and Answers.

AP State Syllabus 9th Class English Solutions Chapter 1C Little Bobby

9th Class English Chapter 1C Little Bobby Textbook Questions and Answers

I. Answer the following questions.

Question 1.
Which is the most humorous action? Give reasons in support of your answer.
Answer:
Stealing Mother Mary’s statue and writing to God as kidnapping is the most humorous action. The reasons are many.

1. Persons are kidnapped; not statues.
2. Mother Mary’s statues are aplenty in so many other churches.
3. God can get back that statue even without giving Bobby a bike.
4. Bobby’s creativity – though used for a wrong cause – is both admirable and humorous.

Question 2.
If you wanted a bike, what would you write to God?
Answer:
If I wanted a bike, I wouldn’t think of writing a letter to God. If I were to write one, would very humbly request God for a bike. I would also explain the need in a detailed way.

Question 3.
Would you like the behaviour of Little Bobby? Why or why not? Give a reason.
Answer:
No, I would not like Little Bobby’s trouble making behaviour. I do not like stealing Mother Mary’s statue. I do not like the action of kidnapping God’s mother and demanding a bike. But I do like Bobby’s honesty in admitting his misbehaviour. I do admire his creativity.

Project Work

Collect data from 30 families (including men, women and children) on the following programmes they watch on TV.
Family Information Sheet

Follow the process given below.
Before conducting survey: Form into three groups.
During the survey: Collect the information to know how frequently people watch different programmes on TV depending on their gender and age.

Each group should collect data from ten families by using the above format.

After the survey:
On the basis of the 10 individual sheets, prepare one consolidated sheet giving the profile of the families visited.
Analyse the results in groups and write a brief report on the result of your survey.

You may use the following phrases:
Very large number of men/women/children (above 75%) ……………………..
Very few number of men/women/children (below 15%) ……………………..
A good number of men/women/children (15%-75%) ……………………..

Consolidated Sheet of Group ONE
Giving the Profile of the 10 Families Visited.

Report of Group ONE :

This report is prepared on the basis of the data collected from ten families on the above mentioned programmes they watch on TV. It reflects how frequently people watch different programmes on TV depending on their gender and age. According to the analysis very large number of women watch movies and cookery programmes. A good number of women, men and children watch movies. Very large number of men watch movies, discussions and film reviews. Only a few number of children and women watch discussions. A large number of children watch games and sports. People of ail age groups and genders spend their time to watch TV.

Consolidated Sheet of Group TWO
Giving the Profile of the 10 Families Visited.

Report of Group TWO :

This report is prepared on the basis of the data collected from ten families on the above mentioned programmes they watch on TV. It reflects how frequently people watch different programmes on TV depending on their gender and age. Very few number of women watch news, games and sports and cartoon programmes. Very few number of children spend their time to watch discussions and cookery programmes. Most of the children watch games and sports. Children watch movies more than women and men. Daily serials and film reviews are great attractions for all. All most all people sit before their TV sets every day.

Consolidated Sheet of Group THREE
Giving the Profile of the 10 Families Visited.

Report of Group THREE :

This report is prepared on the basis of the data collected from ten families on the above mentioned programmes they watch on TV. It reflects how frequently people watch different programmes on TV depending on their gender and age. Games and sports are major attractions for children. Reality shows, cartoon programmes and movies are other important attractions for them. Most of women spend their time to watch daily serials, cookery programmes and movies. Very few women watch news, discussions and games and sports. Men are interested in watching movies, news, games and sports and reality shows. A good number of men like to watch daily serials. All the members of every family spend their time before their TV sets daily.

Little Bobby Summary in English

“Little Bobby” is the story of a naughty boy by Ritcha Rao. He was a troublemaker both at home and school. He one day asked his mother a bike for his coming birthday. Mother wanted Bobby to know how he had been behaving. So she asked Bobby to write a letter to God. She wanted him to write the reasons that made him eligible for a bike. Bobby started writing a letter. But he was not good to deserve a bike. So, he wrote four letters and tore them up as they were not true or helpful. Then he went to the nearby church. He stole the statue of Mother Mary. He came back and wrote to God “I’VE KIDNAPPED YOUR MOM. IF YOU WANT TO SEE HER AGAIN, SEND THE BIKE!”

Little Bobby Glossary

troublemaker (n) : one who causes troubles

deserved (v-past tense) : was eligible to have something

reflect (v) : think about seriously

stumped (v-past tense) : walked angrily and noisily

altar (n) : (The word ‘alter’ (v) is a different word.) place in a prayer hall where statues are placed

kidnapped (v-past tense) : took someone by force with demand for money or things

AP State Syllabus AP Board 9th Class English Textbook Solutions Chapter 1B The Duck and the Kangaroo Textbook Questions and Answers.

AP State Syllabus 9th Class English Solutions Chapter 1B The Duck and the Kangaroo

9th Class English Chapter 1B The Duck and the Kangaroo Textbook Questions and Answers

I. Answer the following questions.

Question 1.
Why did the Duck get bored in life? What did it want to do?
Answer:
The Duck lived in a pond. It cannot hop like a Kangaroo and go round the world. When the Duck saw the Kangaroo going round the places, it felt bored. It wanted to tour places. Limiting to the pond made the Duck unhappy.

Question 2.
What problem did the Kangaroo find with the Duck? How was it solved?
Answer:
The Kangaroo was willing to take the Duck to new places. But it objected to the wet cold feet of the Duck. The Kangaroo said that would make him ill. But the Duck had a solution. It got socks, a coat, and cigars ready to save them from cold.

Question 3.
Who was happy in the end? Why?
Answer:
Both the Kangaroo and the Duck were happy in the end. The Duck was happier as its desire to see places was fulfilled. The Kangaroo too was happy as it could help his friend.

Question 4.
What is the underlying message in the poem?
Answer:
The poem is basically humorous. But it has valuable messages too ! Desire to see new places is a natural way to better oneself. Seeking others’ help promotes cooperative living. Foreseeing the problems and providing solutions is a good lesson.

II. Read the above poem once again and choreograph it as described here under.

Choreography

Choreography is the art of designing sequences of movements or actions for a script or a poem with a voice or a song in background.
Do you know how to process choreography?
Here is the process.
Think of the following.

1. How do we begin the poem?
(Sing the poem three or four times to register the tune and rhythm.)

2. What are the characters in the poem?
(The Duck and the Kangaroo)

3. What is the theme of the poem?
(Wish of the Duck to go round the world)

4. What is the theme of each stanza? (sub themes)

5. Convert the themes into incidents and performable actions.

6. What are the actions involved in the poem?

• Boredom with present life (feelings of boredom, pain)
• Desire to go round the world (miming)
• Wearing socks and smoking cigarettes (joy)
• Displeasure due to wet and cold feet (gestures)
• Sitting on Kangaroo at the end of the tail (miming)
• Joy (facial expression and gestures)

7. Who are the characters involved?
(The Duck, the Kangaroo and other creatures in the pond like frogs, fish, etc.)

8. Where does the incident take place (location)?
(By the side of the pond)

9. Presentation of the choreography on the stage:

• The chorus team sings the poem
• The characters perform their actions
• The action of the Duck and the Kangaroo- expressing boredom, wish, discomfort, joy, etc.
• The actions related to miming, facial expressions and gestures
• Actions related to hopping, sitting, walking, jumping, etc.

The Duck and the Kangaroo Summary in English

‘The Duck and the Kangaroo’ is a poem with a touch of humour. It was the creation of a British poet called Edward Lear. The Duck says that it is bored with its life in the pond.
It wants the Kangaroo to carry it around the world. The Kangaroo says that the Duck’s cold and wet feet will make him ill. The Duck says it has a solution to that problem. It will wear socks. It will also have a coat and smoke. Then the Kangaroo asks the Duck to sit on his tail. The Kangaroo hops around the world thrice with the Duck sitting on his tail. The
poet leaves the question – as to who is so happy? – to the reader!

The Duck and the Kangaroo Glossary

Good gracious! (phr) : an exclamation expressing surprise and emphasis

nasty (adj) : unpleasant

long (v) : have a strong desire

the Dee and the Jelly Bo Lee (n) : wonderful places imagined by the poet

reflection (n) : thinking, consideration

roo-matiz (n) : rheumatism (n) – a disease that makes joints and muscles painful; arthritis

worsted socks : woollen socks

cloak (n) : coat

pale (adj) : low, dull

steady (adj) : remaining in the same position

AP State Syllabus AP Board 9th Class Physical Science Solutions Chapter 5 What is inside the Atom? Textbook Questions and Answers.

AP State Syllabus 9th Class Physical Science Solutions 5th Lesson What is inside the Atom?

9th Class Physical Science 5th Lesson What is inside the Atom? Textbook Questions and Answers

Improve Your Learning

Question 1.
What are the three subatomic particles? (AS 1)
Answer:
The three sub-atomic particles are electrons, protons, and neutrons.

Question 2.
Compare the subatomic particles electron, proton, and neutron. (AS 1)
Answer:

Question 3.
What are the limitations of J.J. Thomson’s model of the atom? (AS 1)
Answer:
The main limitation of J.J. Thomson’s model of atom was that he is unable to explain, how the positively charged particles are shielded from negatively charged particles without getting neutralized.

Question 4.
What were the three major observations Rutherford made in the gold foil experiment? (AS 1)
Answer:
The three major observations Rutherford made in the gold foil experiment were

1. Most of the space inside the atom is empty.
2. All the positive charge must be concentrated in a very small space within the atom called nucleus.
3. The size of the nucleus is very small as compared to the size of the atom.

Question 5.
Sketch Rutherford’s atomic model. Why is Rutherford’s model of the atom called the planetary model? (AS 5)
Answer:

Rutherford’s model is called planetary model because the motion of the electrons around the nucleus resembles the motion of the planets around the sun.

Question 6.
Put tick (✓) against correct choice and cross (✗) against wrong choice: (AS 1)
i) In Rutherford’s gold foil experiment, majority of alpha particles passed directly through the gold foil. This observation leads to which conclusions?
a) The positively charged region of the atom is very small. (✗)
b) The atom must consist of empty space. (✓)
c) The alpha particles makes a direct hit on the positively charged region of the atom. (✗)
d) The positively charged region of the atom is very dense. (✗)

ii) In Rutherford’s gold foil experiment, occasionally the alpha particles veered from a straight line path. This observation leads to which conclusion?
a) The positively charged region of the atom is very small. (✗)
b) The majority of the space in the atom is empty. (✗)
c) The alpha particle makes a direct hit on the positively charged region of the atom. (✗)
d) The positively charged region of the atom is very dense. (✓)

Question 7.
Which one of the following is the correct electronic configuration of sodium? (AS 1)
a) 2, 8
b) 8, 2, 1
c) 2, 1, 8
d) 2, 8, 1
Answer:
d) 2, 8, 1

Question 8.
Give the main postulates of Bohr’s model of an atom. (AS 1)
Answer:
The main postulates of Bohr’s model of atom are

1. Only certain special, discrete orbits of electrons are allowed inside the atom. These orbits or shells are called energy levels.
2. While revolving in these discrete orbits the electrons do not radiate energy and this helps that the electrons do not crash into the nucleus.
3. These orbits or shells are represented by the letters K, L, M, N, ……… or the numbers n = 1, 2, 3, …………

Question 9.
Compare all the proposed models of an atom given in this chapter. (AS 1)
Answer:
In this chapter, four atomic models were discussed. The main postulates of those models are

1. Dalton’s proposal :
a) Atoms are indivisible.
b) Atoms of an element are all identical to each other and different from the atoms of other elements.

2. Thomson’s proposal:
a) An atom is considered to be a sphere of uniform positive charge and electrons are embedded into it.
b) The total mass of the atom is considered to be uniformly distributed throughout the atom.

3. Rutherford’s proposal:
a) All the positively charged material in an atom formed a small dense centre, called the nucleus of the atom.
b) Negatively charged electrons revolve around the nucleus in well defined orbits.
c) Size of the nucleus is very small as compared to the size of the atom.

4. Neils Bohr’s proposal :
a) Electrons are revolving around the nucleus in special, discrete orbits called en¬ergy levels or shells.
b) While revolving in these discrete orbits the electron do not radiate energy and this helps that the electrons do not crash into the nucleus.
c) These orbits or shells are represented by the letters K, L, M, N,…. or the numbers n = 1, 2, 3,

Question 1o.
Define valency by taking examples of nitrogen and boron. (AS 1)
Answer:
Valency: The number of electrons present in outer most orbit of an atom is called its valency. Valency of Nitrogen :
a) Atomic number of nitrogen is 7.
b) The distribution of electrons is 2, 5.
c) The outer most orbit has 5 electrons.
d) Hence its valency should be 5. But it is easier to nitrogen to gain 3 electrons than to loose 5 electrons for becoming octet.
e) Hence the valency of nitrogen is ‘3’.

Valency of Boron :
a) Atomic number of boron is 5.
b) The distribution of electrons is 2, 3.
c) The outer most orbit has 3 electrons.
d) Hence the valency of boron is 3.

Question 11.
State the valencies of the following elements : magnesium and sodium. (AS 1)
Answer:
Magnesium :
a) Atomic number of magnesium is 12.
b) Distribution of electrons is 2, 8, 2.
c) Hence the valency is 2.

Sodium :
a) Atomic number of sodium is 11.
b) Distribution of electrons is 2, 8, 1.
c) Hence the valency is 1.

Question 12.
If Z = 5, what would be the valency of the element? (AS 2)
Answer:
1) If Z = 5, the distribution of electrons is 2, 3.
2) Hence the valency is ‘3’.

Question 13.
Write the atomic number and the symbol of an element which has mass number 32 and the number of neutrons 16 in the nucleus. (AS 1)
Answer:
Mass number (A) = 32 ; Number of neutrons (N) = 16
Number of protons (Z) = A- N = 32-16 = 16
∴ Atomic number =16
The element is sulphur.
The symbol of sulphur is S’.

Question 14.
Cl- has completely filled K and L shells. Explain. (AS 1)
Answer:
Atomic number of Cl is 17, but Cl^– has one more electron when compared with Cl atom. Distribution of electrons in Cl^– is

K shell can accommodate 2 electrons and L shell cab accommodate 8 electrons accord¬ing to the formula 2n2.
Hence the K and L shells are completely filled.

Question 15.
What is the main difference among the isotopes of the same element? (AS 1)
Answer:
The main difference between isotopes of the same element is
a) The number of neutrons is different.
b) Their physical properties are different but the chemical properties are similar.

Question 16.
For the following statements, write T for True and F for False. (AS 1)
a) J.J. Thomson proposed that the nucleus of an atom contains only nucleons.
b) A neutron is formed by an electron and a proton combining together. Therefore, it is neutral.
c) The mass of an electron is 1836 times that of proton.
Answer:
a) False
b) False
c) True

Question 17.
Fill in the missing information in the following table. (AS 4)

Answer:

Question 18.
How do you appreciate the efforts made by scientists to explain the structure of atom by developing various atomic models? (AS 6)
Answer:

• Structure of atom, till today it is mysterious and challenging the scientists.
• We have to appreciate the scientists right from Lavoisier, who proposed law of conservation of mass, Proust who proposed law of constant proportions, John Dalton for his first model of atom, Rutherford for giving planetary model of atom and Neils Bohr for his model of atom.
• Till today scientists are trying to know the existence of more and sub-atomic particles besides electrons, protons and neutrons.
• Hence the efforts of scientists are highly appreciable, for making our lives comfortable and leaving many challenges before us to unveil or discover them.

Question 19.
Geeta got a doubt, “Why does atomic nucleus contain proton and neutrons? Why can’t electrons and neutrons be in it”. Can you help to clarify her doubt? Explain. (AS 1)
Answer:
Nucleus contains protons and neutrons inside it but not electrons and neutrons. If it would have happen, then

1. the alpha particles in the Rutherford’s alpha particle scattering experiment would have not been deflected or scattered.
2. the idea of nucleus would have not been evolved because the mass of electron is negligible, it is most unstable.

Question 20.
Collect information about various experiments conducted and theories proposed by scientists starting from John Dalton to Neils Bohr. Prepare a story with a title “History of atom”. (AS 4)
Answer:
History of atom
John Dalton proposed atomic theory based on law of conservation of mass and law of constant proportion as :

1. Atoms were indivisible.
2. Atoms of an element are all identical to each other and different from the atoms of other elements.

Later on various experiments conducted by Thomson, Goldstein, etc. proved that atom is divisible and consists sub-atomic particles like electrons, protons and neutrons. Based on this J.J. Thomson proposed a model of atom in 1898.

According to Thomson,

1. An atom is considered to be a sphere of uniform positive charge and electrons are embedded into it.
2. The total mass of the atom is considered to be uniformly distributed throughout the atom.
3. The negative and the positive charges are supposed to be balance out and the atom as a whole is electrically neutral.

This model is also called as plum pudding model or watermelon model.

Thomson’s student Ernest Rutherford conducted alpha particle scattering experiment and got the results which were not in favour of Thomson’s model. Based on his experiment, Rutherford proposed a model of atom. According to him,

1. All the positively charged material in an atom formed a small dense centre, called the nucleus of the atom. The electrons were not a part of nucleus.
2. Negatively charged electrons revolve around the nucleus in well – defined orbits like planets revolve around the sun.
3. The size of nucleus is very small as compared to the size of the atom.

This model could not account for stability of atom, as revolving electron must lose energy and eventually crash into the nucleus, as a result matter would not exist in the form that we see it now.

In 1913, Neils Bohr proposed another model to overcome Rutherford’s defect. According to Bohr,

1. Only certain special, discrete orbits of electrons are allowed in side the atom. These orbits or shells are called energy levels.
2. While revolving in these discrete orbits the electrons do not radiate energy and this helps that the electrons do not crash into the nucleus.
3. These orbits or shells are represented by K, L, M, N ………… or the numbers 1, 2, 3,

This model could not predict the spectra of atoms.

Hence this journey continues

9th Class Physical Science 5th Lesson What is inside the Atom? InText Questions and Answers

9th Class Physical Science Textbook Page No. 75

Question 1.
Why are the atoms of different elements different?
Answer:
Nature and properties of elements depends on the arrangement of atoms. We know that different elements behave differently. This is due to the difference in their atoms.

Question 2.
Is there anything inside atom that make them to be same or different?
Answer:
The arrangement of sub atomic particles inside the atom is responsible to make them to be same or different.

Question 3.
Are atoms indivisible?
Answer:
No, atom is divisible. There are many sub-atomic particles inside the atom according to the recent experiments.

9th Class Physical Science Textbook Page No. 77

Question 4.
If an atom consists of sub-atomic particles like protons, neutrons and electrons, how are they arranged in the atom ?
Answer:
The arrangement of sub-atomic particles like protons, neutrons and electrons has been explained by many scientists like Rutherford, Neils Bohr, etc. According to them, atom consists a central mass called nucleus. Nucleus consists protons and neutrons. Electrons revolve around the nucleus in fixed shells.

9th Class Physical Science Textbook Page No. 80

Question 5.
Why is atom stable?
Answer:
In an atom, the number of protons in the nucleus is equal to the number of electrons out side the nucleus. Hence the positive and negative charges in an atom are equal. So, atom is electrically neutral. So, atom is stable. But the stability of atom was explained by Neils Bohr in a different way.

Question 6.
Can you suggest any other arrangement of subatomic particles in the atom which prevents the revolving electron to fall into the nucleus?
Answer:
Electrons have to revolve around the nucleus in definite orbits such that the centripetal and centrifugal forces acting on the electron must be equal in magnitude and opposite direction. Then the revolving electron do not fall into the nucleus.

9th Class Physical Science Textbook Page No. 82

Question 7.
How many electrons can be accommodated in each shell of an atom?
Answer:
The number of electrons that can be accommodated in each shell of an atom depends on the shell number. First shell (K) consists 2 electrons, second (L) shell consists 8 electrons, third (M) shell consists 18 electrons, fourth shell (N) consists 32 electrons, and so on.

Question 8.
Can a particular shell have just one electron?
Answer:
No, shell has just one electron.

Question 9.
What is the criteria to decide number of electrons in a shell?
Answer:
The number of electrons in a shell can be decided by using a formula 2n². (Where n is shell number).

9th Class Physical Science Textbook Page No. 83

Question 10.
What is the valency of oxygen that you can calculate by the method discussed above?
Answer:

• Oxygen has 8 electrons in its atom. The distribution of electrons is 2, 6.
• The outer most shell consists 6 electrons, this number is hear to 8.
• Hence the valency of oxygen is 8 – 6 = 2.

9th Class Physical Science Textbook Page No. 85

Question 11.
Should we consider the number of neutrons as a characteristic of an atom?
Answer:
The mass of an atom which is a characteristic of an atom depends on the number of neutrons and protons that its nucleus contains. Hence the number of neutrons can be considered as a characteristic of an atom.

9th Class Physical Science Textbook Page No. 76

Question 12.
An atom is electrically neutral. But the electrons present in it are negatively charged particles. If only negative charges were present, the atom would not be neutral. Then, why are atoms considered to be neutral?
Answer:

• This is the idea before Rutherford’s model.
• According to Rutherford’s model, number of protons inside the nucleus and number of electrons outside the nucleus are equal.
• Hence the net negative charge is equal to net positive charge. So, the atom is electrically neutral.

9th Class Physical Science Textbook Page No. 80

Question 13.
Compare Rutherford and Thomson’s models of the atom on the following basis :
1) Where is the positive charge placed?
2) How are the electrons placed?
3) Are they stationary inside the atom or moving?
Answer:

1. According to Thomson, the positive charge is uniformly distributed throughout the atom. Whereas according to Rutherford, the positively charged protons are inside the nucleus.
2. According to Thomson, electrons are embedded in the positively charged atom, but according to Rutherford, electrons are revolving around the nucleus in welldefined orbits.
3. According to Thomson, electrons are stable inside the atom but according to Rutherford, electrons are moving inside the atom.

9th Class Physical Science Textbook Page No. 83

Question 14.
Phosphorus and sulphur show multiple valency. See table 2. Why do some elements show multiple valency? Discuss with your Mends and teachers.
Answer:

• For sulphur, the number of electrons in outer most orbit is 6.
• Hence the valency should be (8 – 6 =) 2.
• But sulphur exists in so many forms.
• In the excited state, these 6 electrons also tend to participate in the bond formation.
• Hence sometimes it shows the valency 6. Ex : SO₂, SO₃, etc.
• Same situation happens for phosphorus. Ex . PCl₃, PCl₅, etc.

9th Class Physical Science 5th Lesson What is inside the Atom? Activities

Activity – 1

Question 1.
Sketch the structure of atom as you imagine.

We learnt about electron, proton and neutron.
a) Suppose you had to arrange them in an atom, how do you do it?
Answer:
Many arrangements are possible. Think that atom looks like a room, we can arrange the particles in alternating rows.

b) In how many ways can you arrange these sub-atomic particles in a spherical shape?
Answer:
Protons are positively charged, electrons are negatively charged and neutrons are
neutral. Hence neutrons and protons can be kept nearer and electrons can be kept farther or near the edge of the sphere. This is only an assumption. We can arrange in so many ways like this.

AP State Syllabus AP Board 9th Class Physical Science Solutions Chapter 9 Floating Bodies Textbook Questions and Answers.

AP State Syllabus 9th Class Physical Science Solutions 9th Lesson Floating Bodies

9th Class Physical Science 9th Lesson Floating Bodies Textbook Questions and Answers

Improve Your Learning

Question 1.
A solid sphere has a radius of 2 cm and a mass of 0.05 kg. What is the relative density of the sphere? (AS 1)
Answer:
Radius of the sphere = 2 cm

Question 2.
A small bottle weighs 20 g when empty and 22 g when filled with water. When it is filled with oil it weighs 21.76 g. What is the density of oil? (AS 1)
Answer:
Weight of water = 22 – 20 = 2 gm
Weight of oil = 21.76 – 20 = 1.76 gm

Question 3.
An ice cube floats on the surface of a glass of water (density of ice = 0.9 g/cm3). When the ice melts will the water level in the glass rise? (AS 1)
Answer:
Yes, the water level rises.

Reason :
The ice cube floats on water, because its density is less than the density of water. When ice cube melts, it becomes water, so that the water level rises.

Question 4.
The volume of 50 g of a substance is 20 cm³. If the density of water is 1 g/cm³, will the substance sink or float when placed on the surface of water? What will be the mass of water displaced by the substance? (AS 1)
Answer:

∴ Weight of the water displaced by the substance = 20 g

Question 5.
Find the pressure at a depth of 10 m in water if the atmospheric pressure is 100 kPa. [1Pa = 1 N/m²] [100kPa = 10⁵ Pa = 10⁵ N/m² = 1 atm.] (AS 1)
Answer:
Depth ‘h’ = 10 m ; Atmospheric pressure P₀ = 100 kPa
Density of water p = 1 gm/cm³ = 1 kg/m³
Pressure at a depth ‘h’ is P = P₀ + hρg
= 100 + 10 x 1 x 9.8
= 100 + 98
= 198 kPa

Question 6.
Why do some objects float on the water? And some sink? (AS 1)
Answer:

• Floating or sinking of objects on water depends on two factors.
  a) Relative density
  b) Weight of the water displace by the object
• If the relative density of an object is greater than 1, the object sinks otherwise it floats.
• Eventhough the relative density is greater than 1, if the weight of the water displaced by the object equal to the weight of the object itself, the object floats on the water.

Question 7.
Explain density and relative density and write their formulae. (AS 1)
Answer:
Density :
Density is defined as mass per unit volume.
Density = \(\frac{\text { Mass }}{\text { Volume }}\)

Unit of density is gm/cm³ or kg/m³.

Relative density :
Relative density of an object is the ratio of density of the object to the density of water.

Question 8.
What is the value of density of water? (AS 1)
Answer:
Value of density of water = 1 gm/cm³ (or) 1 kg/cm³.

Question 9.
Find the relative density of wood. Explain the process. (Lab Activity 1) (AS 3)
Answer:
Aim :
To find the relative density of wood.

Materials required :
Overflow vessel, 50 ml measuring cylinder, spring balance, wooden block, water.

Procedure:

1. Weigh the 50 ml measuring cylinder and note its weight.
2. Weigh the wooden block and note its weight.
3. Pour water in the overflow vessel until it starts dripping from its beak.
4. When water stops dripping from the beak, place the 50 ml measuring cylinder under it.
5. Slip the wooden block gently into the overflow vessel, ensuring that the water does not splash out.
6. Once the wooden block is in the overflow vessel, water flows out of the beak and collects in the 50 ml cylinder.
7. Wait till the flow of water from beak, stops.
8. Weigh the cylinder with the water that overflowed and record the weight.

Question 10.
Which is denser, water or milk? (AS 2)
Answer:
The density of water is 1 gm/cc and that of milk is 1.02 gm/cc. Hence milk is slightly denser than water.

Question 11.
What is buoyancy? (AS 1)
Answer:
Buoyancy is the upward force that a fluid exerts on an object less denser than itself.
(or)
Buoyancy is the ability of an object to float in a liquid.

Question 12.
Classify the following things into substances having relative density > 1 and relative density < 1. Wood, iron, rubber, plastic, glass, stone, cork, air, coal, ice, wax, paper, milk, kerosene, groundnut oil, soap. (AS 1)
Answer:

Question 13.
How can you appreciate the technology of making ships float, using the material which sink in water? (AS 6)
Answer:

• We know that a piece of iron sinks in water.
• The relative density of iron is 8.5 which is many times more than water.
• A ship that floats on water is made up of tonnes of iron. It is really wonderful.
• According to the Archimedes principle of buoyancy, any object can float when its weight is equal to the weight of water displaced by it.
• Hence ships are made with a larger surface area so that it displaces the water, whose weight is equal to the weight of loaded ship.
• It involves very sharp scientific calculations and a large engineering technology.
• Really such type of technologies are highly appreciable and the scientists who formulates all these are also really great.

Question 14.
Can you make iron float? How? (AS 3)
Answer:
Yes, we can make iron to float on water.
Procedure:

1. Take a piece of iron and drop it in a vessel of water.
2. We observe that the iron piece sinks in water.
3. Take a thin foil of iron and fold it into four folds.
4. Drop it in water. It sinks.
5. Now unfold the foil and bend it in the form of a bowl. [You can use an iron tin also]
6. Now drop the bowl in water.
7. If floats on water.

Reason:
The weight of water displaced by iron bowl (iron tin) is less than the weight of the iron bowl (iron tin).

Question 15.
How can you find the relative density of a liquid? (Lab Activity – 2) (AS 3)
Answer:
Aim :
To find the relative density of a liquid.

Materials required :
Small bottle of 50 ml capacity (the bottle should weigh not less than 10 gm), spring balance, any liquid (milk or oil or kerosene) about 50 ml.

Procedure:

1. Find the weight of empty 50 ml bottle.
2. Fill the bottle with water and weigh it.
3. Find the weight of 50 ml water.
4. Remove water from the bottle and fill it with any liquid (say milk).
5. Weigh the bottle with liquid.
6. Weight of 50 ml liquid = Weight of bottle with liquid – Weight of empty bottle

Question 16.
Find the relative density of different fruits and vegetables and make a list. (AS 3)
Answer:

• Follow the procedure in Q.No (11) of A.S – (3).
• Use different fruits and vegetables in the place of wooden block.
• Write the observed values in the following table.

Question 17.
Make a lactometer with ball point refill. What would you do to make the refill stand vertically straight? (Activity – 2) (AS 5)
Answer:

• Take an empty ball pen refill. It should have a metal point.
• Take a boiling tube and fill it with water.
• Put the refill in with metallic point inside the water.
• Use a pen to mark the point on the refill to show the part which is above the water surface.
• Pour out the water from the boiling tube and fill it with milk.
• Float the refill in the milk.
• Puf the record mark on the refill, at the point showing the part which is above the surface of the milk.
• These two marks are not at the same place. This is the improvised lactometer.
• We have to attach a small weight at the bottom of the refill to make it stand vertically straight.

Question 18.
Draw the diagram of a mercury barometer. (AS 5)
Answer:

Question 19.
Write a note on Pascal’s discovery in helping to make hydraulic jacks. (AS 6)
Answer:
Pascal’s principle:
External pressure applied to an enclosed body of fluid is transmitted equally in all directions throughout the fluid volume and the walls of the containing vessel.

Use :

1. This principle is used in designing and working of hydraulic jacks.
2. Hydraulic jacks are useful to lift heavy objects like cars and other vehicles in automobile work shops when the vehicles are to be required or repaired.
3. Here very less force is used to lift such heavy vehicles.

Appreciation :

1. Hydraulic jacks are used not only in automobile work shops, but also in so many industries where heavy weights are to be lifted with a little force.
2. All the comforts which we are enjoying now are the efforts of scientists who discovered the laws and principles.
3. Hence we have to appreciate the efforts of Pascal for his contribution in designing these principles.

Question 20.
Write a note on Archimedes discovery of force of buoyancy. (AS 6)
Answer:
Archimedes principle:
When a body is immersed in a fluid, it experiences an upward force of buoyancy equal to the weight of fluid displaced by the immersed portion of the body.

Use :
The principle is used to determine the purity of metals.

Appreciation :

1. This principle was discovered by Archimedes eventually when he was taking bath.
2. With this principle he could solve the problem assigned by the king to him.
3. So many problems in our life may be solved by so many scientific principles discovered by various scientists.
4. You might have heard about falling of the statue of Budha in Hussain Sagar.
5. That statue was lifted by using the principle of buoyancy.
6. Archimedes is thought to be so important as a mathematician that scientists honoured him.
   a) A large hole or crator on the moon is named after Archimedes.
   b) Some mountains on the moon are called the monte – Archimedes.
7. Hence the efforts of Archimedes in discovering such type of principle may be highly appreciated.

Question 21.
You found the relative densities of some solids and some liquids by doing some activities. List the solids and liquids in increasing order of relative density. (AS 4)
Answer:

Question 22.
Iron sinks in water, wood floats in water. If we tie an iron piece to wood piece of the same volume, buritlle and drop it in water, would bundle sink or float? Make a guess and find out whether your guess is correct or wrong with an experiment. Give reasons. (AS 2, AS 3)
Answer:
The body sinks in water.

Reason :
The combined mass of the system increases, so the combined density also increases. Hence the body sinks in water.

Question 23.
Air brakes in automobiles work on Pascal’s principle. What about air brakes? Collect the information about the working process of air brakes. (AS 4)
Answer:

• Air brakes works on the principle of conversion of energy. Generally in trains, while it is moving -fit .produces kinetic energy. This kinetic energy has to be reduced to make the train stop. Here air is used to reduce kinetic energy by converting it into heat energy.
• The system of air brakes in trains has been shown in the figure.
• The important parts are compressor, main reservoir, driver’s brake value, brake pipe, triple value, auxiliary reservoir, brake cylinders, and brake block.

Working:

1. When the driver placed the value in application position, the air pressure in the brake pipe escapes.
2. The loss of pressure is detected by the slide value in the triple value.
3. Now a connection between the auxiliary reservoir and the brake cylinder has been opened and the air in the auxiliary reservoir feeds through into the brake cylinder.
4. The air pressure forces the piston to move against the spring pressure and causes the brakes to be applied to the wheels.

Question 24.
Where do you observe Archimedes principle in daily life? Give two examples.
Answer:
Daily life application of Archimedes principle :

1. Archimedes principle of buoyancy is applied in our daily life in many ways.
2. Fish, human swimmers, ice bergs and ships float follow Archimedes principle of buoyancy.
3. Rise of balloon in air also follows Archimedes principle.
4. While dragging water from a well, the bucket filled with water seems to be weightless till it reaches the surface of the water in the well. This is also due to buoyancy.
5. Swimming of duck in water is also an example of Archimedes principle.

Question 25.
Where do you observe Pascal’s principle in daily life? Give a few examples.
(OR)
Write any one application of Pascal’s principle in daily life.
Answer:
Daily life application of Pascal’s principle :
Pascal’s principle is applied in the working of

1. Hydraulic jacks
2. Hydraulic lifts
3. Hydraulic pumps
4. Hydraulic cranes
5. Siphons
6. Artesian wells
7. Water towers and dams

9th Class Physical Science 9th Lesson Floating Bodies InText Questions and Answers

9th Class Physical Science Textbook Page No. 141

Question 1.
a) Did kerosene float above the water or did water float above the kerosene?
Answer:
Kerosene floats above the water.

b) Which objects float in kerosene?
Answer:
Plastic buttons, match stick, tiny paper balls, wax, etc. floats in kerosene.

c) Which objects sink in kerosene but float on water?
Answer:
Wax sink in kerosene but float on water.

d) Which objects sink in water?
Answer:
Pins, small pebbles, sand, etc. sink in water.

e) Draw a diagram of the tube, showing the results of your activity.
Answer:

f) Why did different objects behave differently?
Answer:
The density of objects is the main reason to behave differently.

9th Class Physical Science Textbook Page No. 144

Question 2.
1) What is the relative density of wood?
Answer:
0.8

2) What is the relative density of glass?
Answer:
1.2

3) Which is denser, rubber or plastic?
Answer:
Rubber is denser than plastic.

4) Which is denser, wood or cork?
Answer:
Wood is denser than cork.

5) Do objects that have a relative density less than 1 Sink in water or float on it?
Answer:
Float on water.

6) Do the objects that sink in water have a relative density less than 1 or more than 1?
Answer:
More than 1.

7) Classify the above materials as denser than stone and less denser than the stone.
Answer:
Denser than the stone : iron, nails.
Less denser than the stone :
eraser, wood, glass slides, plastic cube, Aluminium, glass marbles, cork.

8) What relationship do you find between the relative density of objects and floating sinking of the objects?
Answer:
If the relative density is less than 1 the object of less density will float above the other in the water.

9th Class Physical Science Textbook Page No. 145

Question 3.
1) Which liquid will float on top if groundnut oil is poured over water?
Answer:
Groundnut oil float on the water.

2) If we put a wooden block in kerosene, will it float or sink? Give reasons for your answer.
Answer:

• Wooden block will sink in the kerosene.
• Because, the density of the wooden block is more than the kerosene.

3) A piece of wax floats in water but the same piece of wax sinks in a liquid say liquid ‘X’. Will the relative density of liquid . ‘X’ be less than 1 or greater than 1? How can you say?
Answer:

• The relative density of liquid ‘X’ is less than 1.
• The density of wax is less than 1 because it floats on the water.
• The density of liquid ‘X’ is less than the density of the wax this means less than 1. because wax sinks in that liquid ‘X’.

4) If we mix some water in milk, will the relative density of the mixture be less than or more than the relative density of milk?
Answer:

• We know that relative density of milk is more than 1 and density of milk is more ‘ than water.
• If we mix some water in milk, the density of the mixture will decreases and the relative density will also be less than the relative density of milk.

5) If we take two bottles of equal volume and pour pure milk in one and milk mixed with water in the other, which one will be heavier?
Answer:

• Pure milk is heavier than water mix milk.
• This is due to density of milk is more than water.

9th Class Physical Science Textbook Page No. 151

Question 4.
Why is the height of mercury column nearly 76 cm in the tube?
Answer:
Air pressure is the weight of air in the atmosphere above the reservoir (bowl of mercury). So, the level of mercury continues to change until the weight of mercury in the glass tube is exactly equal to the weight of the air above the reservoir, which is 76 cm.

9th Class Physical Science Textbook Page No. 154

Question 5.
What happens if we replace this cylindrical liquid column with another object which is made up of a material whose density is equal to the density of liquid?
Answer:
We know that the pressure difference in the liquid,
P₂ – P₁ = hρg

Since F = PA and W = mg
We get F = W (Values of displaced liquid)

1. Here F’ is the force applied on the object and ‘W’ is the weight of the liquid.
2. So, the”force applied on the object by the liquid is equal to the weight of the displaced liquid.

9th Class Physical Science Textbook Page No. 155

Question 6.
Why does the stone lose weight when it is immersed?
Answer:

• Suspend a stone from a spring balance. Note the reading of the spring balance.
• Take a beaker half-filled with water.
• Now immerse the stone in the water, note the reading of the spring balance.
• We notice that the stone, when immersed appears to lose some weight.
• The immersed stone appears to lose weight because the force of buoyancy.
• Thus the apparent loss of weight must be equal to the force of buoyancy acting on the immersed stone.

9th Class Physical Science Textbook Page No. 142

Question 7.
Let us suppose you have two blocks and you do not know what material they are made of. The volume of one block is 30 cm3 while the other is 60 cm3. The second block is heavier than the first. Based on this information, can you tell which of the two blocks is denser?
Answer:
No, we cannot say which of the two blocks is denser, because any one of the quantity
i. e., either volume or weight must be same.

9th Class Physical Science Textbook Page No. 153

Question 8.
a) What would happen if Toricelli’s experiment is done on moon?
b) A stopper is inserted in the small hole of the glass tube of the mercury barometer below the top level of the mercury in it. What happens when you pull out the . stopper from the glass tube?
c) Why don’t we use water instead of mercury in Toricelli experiment? If we are ready to do this experiment, what length of tube is needed?
d) Find the weight of the atmosphere around the earth (take the radius of earth as 6400km)
Answer:
a) If Toricelli’s experiment had been done on moon, the height of mercury column will be zero. Because there is no atmosphere on the moon.

b) The mercury level does not change, because there is vacuum above the mercury level. Hence no pressure is on the mercury. Also, the weight of mercury column must be equal to the air pressure above the reservoir. Hence there will be no change in the height of the mercury column.

c) We cannot use water instead of mercury in Toricelli experiment because, if we want to use water, we have to take the glass tube of length nearby above 10 m, which is inconvenient.
If water is taken,
P₀ = ρhg
1 01 yin5
1.01 × 10⁵ = 1 × 10³ × h × 9.8 ⇒ h = = 0.1030 × 10² = 10.3 m

d) Weight of atmosphere = Atmospheric pressure x Surface area of the earth

9th Class Physical Science Textbook Page No. 157

Question 9.
a) Why is it easier for you to float in saltwater than in freshwater?
b) Why is there no horizontal buoyant force on a submerged body?
c) Two solid blocks of identical size are submerged in water. One block is iron and the other is aluminium. Upon which is the buoyant force greater?
d) A piece of iron when placed on a block of wood, this makes the wood to float lower in the water. If the iron piece is suspended beneath the wood block, would it float at the same depth? Or lower or higher?
Answer:
a) Salt water is denser than freshwater.
b) Buoyant force is the upward force only. The body is submerged means, its weight is more than the buoyant force. Here there will be no horizontal buoyant force.
c) Buoyant force on iron block is more than that of aluminium block.
d) It floats on higher depth than in the first case.

9th Class Physical Science 9th Lesson Floating Bodies Activities

Activity – 1

Question 1.
Comparing density – relative density.
Take two test tubes of the same size and fill one to the brim with water and the other with oil.
a) Which will weigh more?
Answer:
The test tube with oil will weigh more.

b) Which liquid is denser?
Answer:
Oil is denser than water.
Take two equal sized blocks made of wood and rubber.

c) Which of these two blocks is heavier?
Answer:
Wooden block is heavier.

d) Which one is denser?
Answer:
Wooden block is denser than rubber.

Activity – 3

Question 2.
Do the objects denser than water float in it? Prove it with an activity.
Answer:

• Collect some objects listed in the table below.
• Place them one by one in a glass of water and observe whether they sink or float in water.
• Record your observations in the table.

Observations:

• Find the relative densities of all the objects.
• We observe that some objects floats and some objects like iron nail, glass marble, stone sinks in water.
• Geometry box made of iron floats on water, though its relative density is greater than 1. This is due to its larger surface area.
• Geometry box made of iron floats on water though it is made up of a substance denser than water.
•  We can say that the floating or sinking of an object does not depend not only on its relative density, but also its surface area which displaces the water.

Activity – 4

Question 3.
Show that for a floating object, the weight of the object is equal to the weight of water displaced by it.
Answer:

• Take a beaker and weigh it. Note down its weight.
• Fill water in an overflow jar, wait until the water stops dripping from the outlet of the overflow jar.
• Now place the beaker below the outlet of the overflow jar.
• Take a wooden block, moisten it with water and gently drop it into the overflow jar.
• Water will flow out of the overflow jar and collects in the beaker kept under the overflow jar.
• Measure the weight of beaker with water.
• Subtract the weight of beaker from this. The value gives the weight of water displaced by wooden block. Note it.
• Now remove wooden block from the overflow jar, make it cry and weight.
• We can observe that the weight of wooden block is equal to weight of water displaced by it.
• Do the same experiment with some other substances and record your observations in the table.

Activity – 5

Question 4.
Explain how does metal aluminium floats on the water with an activity.
Answer:

• Take a small sheet of aluminium foil.
• Fold it four or five times, pressing the foil tight after each fold.
• We can find that the aluminium foil will sink in the water.
• Now unfold the aluminium foil and make it as a small bowl.
• We can find that the bowl will float on the water.
• The metal bowl displace larger amount of water than a metal piece.
• Weight of the displaced water is more than the metal sheet.
• So, bowl will float on the water.

Activity – 6

Question 5.
Prove that the water exerts upward force on objects.
Answer:

1. Take an empty plastic bottle.
2. Put the cap on it tightly.
3. Place the bottle in a bucket of water.
4. The bottle will float.
5. Push the bottle into the water by your hand as shown in figure.
6. We feel some upward force.
7. Try to push it further down. We feel increase in the upward force.
8. Now release the bottle.
9. It bounce back to the surface of water.
10. Here the upward force of water a real, observable force.
11. This force acting on unit area of the surface of an object is called static pressure of the water.

Activity – 7

Question 6.
Describe an activity to observe the air pressure.
Answer:

1. Take a glass tumbler.
2. Stick some cotton at the bottom of it.
3. Immerse it inversely in water upto the bottom of the container as shown in figure.
4. Take out the tumbler from water.
5. We observe that the cotton attached at the bottom of the tumbler is not wet.
6. This is due to the force of air which is applied on water by the air present in the tumbler and stops water from entering the tumbler.
7. This force on unit area of water is the pressure of air.

Activity – 8

Question 7.
How can you measure the force of buoyancy and how much?
(OR)
Why does and stone lose weight when it is immersed in water?
Answer:

• Suspend a stone from a spring balance.
• Note that the reading of the spring balance.
• The reading gives the weight of the stone.
• Take a beaker half filled with water.
• Now immerse the stone in the water.
• Note the reading of the spring balance.
• The reading gives the weight of the immersed stone.
• We may notice that the stone, when immersed, appears to lose some weight.
• The immersed stone appears to lose weight because the force of BUOYANCY, exerted on the stone by the water in the upward direction.
• Thus the apparent loss of weight must be equal to the force of buogancy acting on the immersed stone.
• The lose of weight of stone is equal to weight of the water displaced by the stone, this is the force of buoyancy.

Activity – 9

Question 8.
‘State and prove Archimedes principle of buoyancy.
Answer:

Archimedes principle :
Archimedes principle states that when a body is immersed in a fluid, it experiences an upward force of buoyancy equal to the weight of fluid displaced by the immersed portion of the body.

Proof:

1. Suspend a stone from a spring balance.
2. Note the reading on the spring balance. This reading is the weight of the stone.
3. Take an overflow jar with water and place a graduated beaker below the beak as shown in the figure.
4. Now immerse the stone in the water and note the reading on the spring balance.
5. Measure the volume of the water that overflows into the graduated beaker.
6. The reading of the spring balance gives the weight of the immersed stone.
7. The beaker reading gives the volume of water displaced by the stone.
8. The difference in the two readings of spring balance gives the apparent loss of weight of the stone.
9. Now weigh the water in the graduated beaker.
10. We observe that the apparent loss of weight of the stone is equal to the weight of the water displaced by the stone.
11. Hence Archimedes principle is proved.

AP State Syllabus AP Board 9th Class Social Studies Important Questions Chapter 3 Hydrosphere.

AP State Syllabus 9th Class Social Studies Important Questions 3rd Lesson Hydrosphere

9th Class Social 3rd Lesson Hydrosphere 1 Mark Important Questions and Answers

Question 1.
How are we polluting oceans today? (SA-III: 2016-17)
Answer:
We are polluting oceans today by dumping plastic, other forms waste and other industrial waste.

Question 2.
How can you appreciate the oceans as resources? (SA-II: 2017-18)
Answer:

• Ocean waves are used for generating power.
• Ocean floor is mined for oils.
• Oceans also provide with gems and pearls.

Question 3.
Write any two factors that affect the salinity of oceans. (SA-II: 2018-19)
(OR)
Write any two factors which effect salinity in water bodies? (SA-I: 2018-19)
Answer:
Salinity in water bodies is affected by evaporation, precipitation, ice formation, ice melting and temperature also.

Question 4.
Give any two examples of warm ocean currents. (SA-I: 2019-20)
Answer:
Two examples of warm ocean currents :
(a) Gulf stream,
(b) Kuroshio

9th Class Social 3rd Lesson Hydrosphere 2 Marks Important Questions and Answers

Question 1.
(SA-I: 2019-20)
a) Water distribution on earth
b)Fresh water consumption by humans
a) What percentage of the total water on the Earth is available for consumption?
Answer:
0.75% or 2.5%

b) Which activity of humans need maximum water?
Answer:
Agriculture.

9th Class Social 3rd Lesson Hydrosphere 4 Marks Important Questions and Answers

Question 1.
Describe the stages of water cycle.(SA-II: 2017-18)
(OR)
Explain various stages of Hydrological cycle. (SA-I: 2018-19)
(OR)
Draw the hydrological cycle and describe the stages involved in it.

Answer:
There are six stages of water cycle. They are –
a) Evaporation :

• The process by which water changes from liquid to gas by using sun’s energy is called evaporation.
• Land, lakes, rivers and oceans send up a steady of water vapour and plants lose water to the air through transpiration.

b) Transportation :

• The movement of water through the atmosphere specifically from over the ocean to land in the form of clouds is transportation.
• Clouds are propelled from one place to another by either the jet stream, surfaces based circulations like land and sea breezes or other mechanisms.

c) Condensation :
The transported water vapour eventually condenses forming tiny droplets and clouds.

d) Precipitation :

• The primary mechanism for transporting water from the atmosphere to the surface of the earth is precipitation.
• When the clouds meet cool air over land precipitation is triggered in the form of rain, sleet or snow and thus water reaches the ground.

e) Run off:

• Most of the water which returns to land flows down hills as run off.
• Some of it penetrates into the land and charges ground water while the rest, as river flow, returns to the oceans where it evaporates.

f) Groundwater :
Under special circumstances, groundwater can even flow upward in artesian wells.

Question 2.

Read the above table and answer the following questions. (SA-II: 2017-18)
1. Which ocean is also known as Southern Ocean?
2. Which ocean separate the America from Europe and Africa?
3. Which continents are separated by the Indian Ocean?
4. What are the land masses in Oceania?
Answer:

1. Antarctic ocean is know as Southern ocean.
2. The Atlantic ocean separates the America from Europe and Africa.
3. The Indian ocean washes upon Southern Asia and separates Africa and Australia.
4. Australia, New Zealand, Papua New Guinea are the land masses in Oceania.

Question 3.
“Water is considered a renewable resource”. Explain this statement.” (SA-I: 2019-20)
Answer:

• Water is considered a renewable resource because it cycles through the Earth system.
• It falls as precipitation.
• Then gets absorbed or run off.
• If it is absorbed, it can go deep into the ground or it can be taken up by plants.
• Plants return water to the atmosphere through transpiration.
• The water that goes deep into the ground can eventually run off into surface bodies of water like lakes and streams.
• The water that runs off can be evaporated, or it can run into lakes and streams.
• The water in lakes and streams can be evaporated, returning it to the atmosphere, where it can precipitate again.

9th Class Social 3rd Lesson Hydrosphere Important Questions and Answers

Question 1.
What is an Ocean? Write a brief essay on the ocean.
Answer:
The huge water bodies are called Oceans. There are five oceans on the earth. They are the Pacific ocean, the Atlantic ocean, the Indian ocean, the Southern (Atlantic) ocean and the Arctic ocean.

The ocean basins are in many ways similar to the land surface. There are submarine ridges, plateaus, canyons and terraces. Ocean floor is simply divided into four layers. They are continental shelf, continental slope, deep sea plain and oceanic deep.

Ocean water is salty. Most of the salt in the oceans comes from land. Over millions of years rain, rivers and streams have washed over rocks containing the compound Sodium Chloride and carried into the sea. The total content of dissolved salts in sea water is called salinity. It is usually expressed as parts per thousand (PPT). Average salinity of the oceans is 35%0. The salinity of ocean water depends mainly on evaporation and precipitation.

The little variations in ocean temperature show great effect on land temperatures. South west monsoon in India is affected by ‘El Nino’ and ‘La Nino’. These are the effects caused by the changes in temperature in the Pacific ocean. Normally, the temperature in oceans varies from – 2°C to 29°C.

The general movement of a mass of water in a fairly defined direction over great distance is called an ocean current. Based on temperature ocean currents may be classified into cold currents and warm currents. Generally warm currents flow towards the poles, cold currents flow towards the equator. Centrifugal force, effects of winds, effects of precipitation, effect by solar energy are the causes of ocean currents.

Oceans have many uses for man. They are the store houses of fish. Oceans are the sources of Chlorine, Fluorine, Bromine and Iodine. Tides and waves of the oceans are the sources of renewable energy. Oceans are sources for rainfall. They act as international highways. Rock petroleum and natural gas are extracted under oceans. Minerals such as sand, gravel, manganese, copper, nickel, etc., are mined from oceans.

Thus without oceans Ijfe of man is impossible.

Question 2.
Describe the salinity of the oceanic water.
Answer:

• Ocean water is salty.
• Most of the salt in the oceans comes from land.
• Over millions of years rain, rivers and streams have washed over containing the compound Sodium Chloride (NaCl) and carried into the sea.
• The total content of dissolved salts in sea water is called salinity.
• The salinity of oceanic water depends mainly on evaporation and precipitation.
• In coastal regions salinity is influenced by the fresh water flow from rivers.
• In polar regions salinity is influenced by the process of freezing and thawing of ice.
• Salinity is usually expressed as parts per thousand (%0) or PPT.
• The average salinity of the oceans is 35%0.
• Lake Van of Turkey is the water body with the highest salinity.

Question 3.
Describe the temperature of oceanic water.
Answer:

• When compared to land the temperature on oceans does not show more variations.
• Ei Nino and La Nino are the effects caused by the changes in temperature in the Pacific Ocean.
• The activeness of South West monsoon in India is affected by Ei Nino and La Nino.
• The ocean temperature is influenced by latitudes, winds and ocean currents, unequal distribution of land and the change of seasons.
• Normally, the temperature in oceans varies from – 2°C to 29°C.
• The highest temperature is recorded in inland seas.
• The temperature is the highest in Red Sea, i.e. 38° C.
• As one goes deep inside the oceans, the temperature rapidly decreases for every 1 km and remains stable.
• The temperature is stable at the foot of ocean i.e., 1.8° C.

Question 4.
What are the ocean currents? How are they formed?
Answer:
1. The general movement of a mass of water in a fairly defined direction over great distance is called ocean current.

2.Causes that lead to the formation of ocean currents are :
a) Centrifuge! Force :
The centrifugal force at the equator is greater than that at the poles. The variation of these forces makes the equatorial water to move towards the poles.

b) Effect of Winds :
The stresses due to wind and the wind movement modifies the the theoretical direction of currents. Due to the frictional gliding of winds water is dragged along the wind direction. Thus a 50 miles per hour wind will produce a current whose velocity is 0.75 miles per hour.

c) Effect of Precipitation :
Since the level of sea is higher water moves north and south from the equator.

d) Effect of Solar Energy :
Heating by solar energy causes the water to expand near the equator. Hence near the equator the ocean water is about 8 cm higher in level than in the middle latitudes. This causes a very slight gradient and water tends to flow down the slope.

e) Salinity, density differences, melting of ice also affect the ocean currents.

Question 5.
How are the oceans useful to mankind?
Answer:

1. Oceans are store houses for fish.
2. Since early times man depended on oceans for food.
3. Dogger Bank North Sea, Grand – bank, New found land are famous fishing regions.
4. Chlorine, Fluorine, Bromine and Iodine are found in oceans.
5. Tides and waves are non-renewable energy resources.
6. Oceans are sources for rainfall.
7. Oceans act as international highways.
8. Sources for civilizations : Greek civilization, Rome civilization all flourished on banks of rivers and oceans.
9. Rock petroleum, Natural gas are extracted under oceans.
10. Oceans are mined for minerals, salt, sand, gravel, manganese, copper, nickel, etc.

Question 6.
Why is the earth called the blue planet?
Answer:

• Planet earth is called the ‘Blue planet’ due to the abundant water on its surface.
• About 71% of the earth is covered with water.
• If we look at earth from outer space, we can see the earth almost entirely blue.

Question 7.
What is the importance of continental shelf?
Answer:

1. The continental shelf with depth up to 200 mts occupied about 7.6% of the oceans area.
2. It is the border zone between land and sea.
3. Continental shelf is most important to
   a) Fish wealth is more in this region.
   b) Rock petroleum, natural gas are found here.
   c) Building sea port is possible here.

Question 8.
What are Oceans?
Answer:
The huge water bodies are called Oceans.

Question 9.
What is ocean current?
Answer:
The general movement of a mass of water in a fairly defined direction over great distance is called ocean current. –

Question 10.
What is meant by evaporation?
Answer:
Evaporation: The process by which water changes from liquid to gas by using sun’s energy is called evaporation.

Question 11.
What is meant by transportation?
Answer:
Transportation:
The movement of water through the atmosphere specifically from over the ocean to land in the form of clouds is called transportation.

Question 12.
Where do we find trenches? What is their significance?
Answer:

• Contrary to our expectations, most of the deepest trenches are not located in the midst of oceans.
• They are found more close to the continents.
• They are very significant in the study of plate movements.

Question 13.
Which part of ocean floor is suitable for building seaport? Why?
Answer:

• Continental shelf of ocean floor is suitable for building seaport.
• The continental shelf with depth upto 200 m.
• It is the border zone between land and sea.
• It will be useful in anchoring the ships.

Question 14.
Do you think the rain we get is in any way related to hydrological cycle?
Answer:

• Yes. I think the rain we get is related to hydrological cycle.
• It is a part of precipitation, which constitutes in hydrological cycle.
• It is the fourth stage of the six stages in hydrological cycle.

Question 15.
What are the factors that affect the movement of ocean currents?
Answer:
The factors that affect the movements of ocean currents are –

1. The centrifugal force
2. The winds
3. The precipitation
4. The solar energy
5. Salinity
6. Differences in density
7. Melting of ice etc.

Question 16.
Write about continental slope.
Answer:

• The continental slope is spread from 200 mts to 3000 mts depths of oceans.
• It comprises of 15% of the ocean area.
• Submarine canyons are observed in this region.

Question 17.
Write about the classification of Ocean currents.
Answer:
1. Ocean currents may be classified on the basis of temperature as –
(a) Cold Currents
(b) Warm Currents

2. Ocean currents may be classified on the basis of speed as –
(a) a stream
(b) a drift

Question 18.
“From ail the sources of water reaching the earth, less than 1% of water is useful to man” – Interpret the statement.
Answer:
Of the total volume of water on earth only 2.75% is fresh water. Most fresh occurs in the form of permanent ice, snow locked up in the Antarctica and Arctic and in the mountain regions. The principal sources of water for human use are lakes, rivers, soil moisture and relatively shallow ground water basin. The usable portion of these sources is only about less than 1% of all fresh water.

Question 19.
“RF = RO + ET” – Explain the equation.
Answer:

• The total amount of water present on the earth surface remains constant but undergoes continuous transformation from water vapour to liquid.
• This equation is also called water balance equation.
• That means the amount of water received from rainfall is equal to the total amount of water runs off and the amount of water that is lost in evapotranspiration.
• Thus the equation Total Rain Fall = Total Run Off+Total water lost in Evapotranspiration.

Question 20.
in which ways oceans are being exploited by us, today?
Answer:

• Today oceans have also fallen victim to our exploitation.
• Many large fish like whales have been disappearing.
• Oceans have also become dumping ground for our plastic and other forms of faste.

Question 21.
Usually oceans have salinity of 35%. But being part of Atlantic ocean, how come Baltic sea has salinity of 3-15%?
Answer:

1. Baltic sea is enclosed by Scandenavia (Norway, Sweden), Finland, Baltic countries and North European plain.
2. It has major inflows from rivers like Oder, Vistula, Neva, Narva, Jome, Neman, Kemijoki and Dangava.
3. Only outlets towards danist areas.
4. As its coastal regions are in respect of fresh waters resulting in lower salinity.

Question 22.
Lake Van of Turkey experiences harsh winters with -300C. Why do you think its water never gets freezed?
Answer:

• Lake Van is fed by streams descending from surrounding mountains.
• It has no outlet, as outlet once present was closed by volcanic eruption.
• Water here is with a pH value of 9.7 – 9.8.
• It is situated at an altitude of 5380 ft.
• But because of its salinity of 330%, (oceans have 35% salinity) it is free from freezing.

Question 23.
The table below shows the descending order of the oceans in terms of size.

1) What is the largest ocean on the earth?
Answer:
The Pacific ocean.

2) Which ocean is considered as the extension of three important oceans?
Answer:
The Antarctic ocean.

3) What is the smallest ocean on the earth?
Answer:
The Arctic ocean.

4) Which ocean separates America from Europe and Africa?
Answer:
The Atlantic ocean.

5) Where is the Indian Ocean?
Answer:
To the South of Asia.

Question 24.
“The activeness of South west monsoon in India is affected by El Nino and La Nino”. Prove the statement.
Answer:

• El Nino and La Nino are the names given to the changes in winds in the Pacific Ocean.
• El Nino and La Nino are formally called ‘The small boy’ and ‘The little girl’.
• La Nino and El Nino come about when the waters of the eastern and central Pacific Ocean along the equator become usually cold or warm.
• These changes in the Pacific produce swings in atmospheric pressure, winds, temperature and rainfall that have a global impact.
• For India La Nino is often a cause for concern because of its adverse impact on the South west monsoon.
• The El Nino on the other hand is often beneficial for the monsoon especially in the latter half of the season.
• Because of global warming the temperature of the western Pacific is influencing the effect La Nino.

Question 25.
Can you say what the temperature at the foot of the Pacific ocean is?
Answer:

• Normally, the temperature in oceans varies from -2°C to 29°C.
• As one goes deep inside the oceans the temperature rapidly decreases for every 1 km and then it remains stable.
• The temperature is stable at the foot of the ocean, i.e. 1.8°C.
• Therefore the temperature at the foot of the Pacific ocean is 1.8°C.

Question 26.
“The government of Maldives held its first underwater cabinet meeting at a depth of 20 feet off the coast just north of the capital Male. Maldives wanted to attract the attention of the world to the dangers of global warming and sea-level rise. This is a matter of great concern not only for the Maldives but also for all the countries in the World”.
Basing on the information given above – frame a thought provoking question on the issue.
Answer:
What are the causes that lead to the sea level rise ? What should we do to prevent it?

Question 27.
Why do we call the earth as blue planet?
Answer:

• 71% of the earth is covered with water.
• Hence it appears as blue in the photographs taken from the moon.
• So we call the earth as blue planet.

Question 28.
Without oceans life of the man is impossible. Discuss it.
Answer:

• Oceans are international highways hence facilitate imports and exports among different countries.
• Oceans are sources of rainfall. Much of the evaporation takes place from oceans and comes to earth in the form of rainfall.
• They are the source of sea food which is staple food for some people.
• Oceans are warehouses of minerals like Petroleum, Natural Gas, Manganese etc., which are necessary for industrial development.

Hence life of the man is impossible without oceans.

Question 29.
Observe the map.

Now, answer the following questions.
1) Which ocean separates America from Africa and Europe?
Answer:
Atlantic ocean.

2) Name ocean that separates Africa and Australia.
Answer:
Indian ocean.

3) Which is the ocean that encircles Australia?
Answer:
Pacific ocean.

4) Which ocean is there to the south of India?
Answer:
Indian ocean.

Question 30.
Locate the following oceans in the world map given below.
1) The Pacific ocean
2) The Atlantic ocean
3) The Indian ocean
4) The Arctic ocean
5) The Antarctic Ocean
6) The Baltic sea
7) The Red sea

Question 31.
Describe any one impact of ocean currents for the region you live.
Answer:
The Indian Monsoon current refers to the seasonally varying ocean current regime found in the tropical regions of the nothern Indian ocean. The seasonally reversing open ocean currents that pass through south of India are referred to as the winter monsoon current and the summer monsoon current, alternately the north-east monsoon current and the southwest monsoon current.

India receives rainfall due to these currents.

Question 32.
Without oceans life of man is impossible. Discuss it.
Answer:
Throughout the history man is directly or indirectly influenced by the oceans. Oceans have many uses for man.

1. Since early times man depended on oceans for food. Oceans are store houses for fish.
2. Ocean is a source of valuable minerals. Chlorine, Fluorine, Bromine and Iodine are found in oceans.
3. Rock petroleum, Natural gas are extracted under oceans.
4. Oceans are mined for mineral salt, sand, gravel manganese, copper, nickel etc.
5. Some biological products of oceans are also commercially used. For example, pearls taken from oysters are used in jewellery.
6. Shells and corals have been widely used as source of building material.
7. Tides and waves are renewable energy sources.
8. Oceans are sources of rainfall.
9. Oceans act as international highways.
10. Many great civilizations such as Greek civilization, Rome civilization all flourished on the banks of rivers and oceans.

There are many more uses for man from oceans. Hence we can say without oceans life of man is impossible.

AP State Syllabus AP Board 9th Class Physical Science Solutions Chapter 3 Is Matter Pure? Textbook Questions and Answers.

AP State Syllabus 9th Class Physical Science Solutions 3rd Lesson Is Matter Pure?

9th Class Physical Science 3rd Lesson Is Matter Pure? Textbook Questions and Answers

Improve Your Learning

Question 1.
Which separation techniques will you apply for the separation of the following? (AS 1)
a) Sodium chloridfe from its solution in water.
b) Ammonium chloride from a mixture containing sodium chloride and ammonium chloride.
c) Small pieces of metal in the engine oil of a car.
d) Different pigments from an extract of flower petals.
e) Butter from curd.
f) Oil from water.
g) Tea leaves from tea.
h) Iron pins from sand.
i) Wheat grains from husk.
j) Fine mud particles suspended in water.
Answer:

Question 2.
Write the steps you would use for making tea. Use the words given below and write the steps for making tea. (AS 7)

Answer:

• Take a cup of milk (solvent) in a tea kettle.
• Add one table spoon of sugar (solute), and one table spoon of tea powder (insoluble) to the solvent.
• Heat the tea kettle on the stove.
• The sugar (solute) dissolves in the milk (solvent) and the tea powder remains undissolved.
• Now filter the solution so formed.
• The filtrate is the tea (solution).
• The residue remained in the sieve is the insoluble component of tea powder.

Question 3.
Explain the following giving examples. (AS 1)
a) Saturated solution
b) Pure substance
c) Colloid
d) Suspension
Answer:
a) Saturated solution :
When no more solute can be dissolved in the solution at a certain temperature, it is said to be a saturated solution.

In a saturated solution, equilibrium with the undissolved solute at a certain temperature.

Ex :

1. Take 50 ml of water in a cup.
2. Add one spoon of sugar to the cup and stir still it dissolves.
3. Keep on adding sugar to the water in the cup and stir till no more sugar can be dissolved.
4. The solution so formed is a saturated solution.

b) Pure substance :
A substance is pure i.e., homogeneous if the com-position doesn’t change, no matter which part of the substance we take for examination.

Ex :

1. Take a small part of pure gold biscuit as a sample.
2. The composition is found to be same throughout it.

c) Colloid :
Colloids are heterogeneous mixtures in which the particle size is too small to be seen with the naked eye, but is big enough to scatter light.
Ex : Milk, butter, cheese, cream, gel, etc.

d) Suspension :
Suspension is a heterogeneous mixture in which the solute particles didn’t dissolve and the particles are visible to naked eye.
Ex : Syrups, chalk powder mixed with water, etc.

Question 4.
Classify each of the following as a homogeneous or heterogeneous mixture. Give reasons. (AS 1)

Answer:

Question 5.
How would you confirm that a colourless liquid given to you is pure water? (AS 1)
Answer:

• Observe the smell. We should not find any smell.
• Observe with a naked eye we should not find any suspended particles or fumes or air bubbles.
• Pass a beam of light. It should not scatter.
• The temperature should be normal.
  Then the given colourless liquid is pure water.

Question 6.
Which of the following materials fall in the category of a “pure substance”? Give reasons. (AS 1)
a) Ice
b) Milk
c) Iron
d) Hydrochloric acid
e) Calcium oxide
f) Mercury
g) Brick
h) Wood
i) Air
Answer:

• Except brick and wood remaining materials given in the list can be treated as pure substances.
• Take any small part of ice, milk, iron, hydrochloric acid, calcium oxide, mercury and air and test for their components.
• We find that the composition is same throughout them.

Question 7.
Identify the solutions among the following mixtures. (AS 1)
a) Soil
b) Sea water
c) Air
d) Coal
e) Soda water
Answer:
The solutions are : sea water, air and soda water.

Question 8.
Which of the following will show “Tyndall effect”? How can you demonstrate “Tyndall effect” in them? (AS 1, AS 3)
a) Salt solution
b) Milk
c) Copper sulphate solution
d) Starch solution
Answer:
Milk shows Tyndall effect.

Demonstration :

1. Prepare the milk, copper sulphate, salt and starch solutions in different beakers.
2. Allow a beam of light through each of them.
3. The path of the light beam is clearly visible to us through milk.
4. The path of the light beam is not visible through remaining.
5. This experiment will be effective if it is performed in a dark room.

Question 9.
Classify the following into elements, compounds and mixtures. (AS 1)
a) Sodium
b) Soil
c) Sugar solution
d) Silver
e) Calcium carbonate
f) Tin
g) Silicon
h) Coal
i) Air
j) Soap
k) Methane
l) Carbondioxide
m) Blood
Answer:

Question 10.
Classify the following substances in the below given table. (AS 1)

Answer:

Question 11.
Take a solution, a suspension, a colloidal dispersion in different beakers. Test whether each of these mixtures shows the Tyndall effect by focusing a light at the side of the container. (AS 3)
Answer:

• Take sugar solution (solution), starch solution (suspension) and milk solution (colloidal dispersion) in three different beakers.
• Focus a beam of light by torch or a laser beam at the side of each container and observe.
• We can see that the path of beam of light is clearly visible through all the solutions.
• Hence all the three solutions show ‘Tyndall effect”.

Question 12.
Draw the figures of arrangement of appatus for distillation and fractional distillation. What do you find the major difference in these apparatus? (AS 5)
Answer:

The main difference between these two apparatus is that a fractionating column is fitted in between the distillation flask and the condenser.

Question 13.
Determine the mass by mass percentage concentration of a 100 g salt solution which contains 20 g salt. (AS 1)
Answer:
Mass of salt = 20 g; Mass of salt solution = 100g

Question 14.
Calculate the concentration in terms of mass by volume percentage of the solution containing 2.5 g potassium chloride in 50 ml of potassium chloride (KCl) solution. (AS 1)
Answer:
Mass of potassium chloride = 2.5 g
Volume of potassium chloride solution = 50 ml

9th Class Physical Science 3rd Lesson Is Matter Pure? InText Questions and Answers

9th Class Physical Science Textbook Page No. 40

Question 1.
Can you give few more examples of this kind?
Answer:
Some more examples of homogeneous mixtures are sugar solution, lemon squash, fruit juices, syrups and tonics used in medicine, etc.

Question 2.
Can you prove this with an experiment?
Answer:

• Take some thick milk in a test tube.
• Pass a beam of light from torch or a laser light.
• We cannot observe the path of light through the solution.

Question 3.
If the solution is diluted, can the path of light be visible?
Answer:

• Take some thick milk in a test tube.
• Dilute it by adding some water.
• Now pass a beam of light from torch or a laser light.
• We cannot observe the path of light through the solution.

Question 4.
What would happen if you add a little more solute to a solvent?
Answer:
The solution becomes concentrated.

Question 5.
How do you determine the percentage of the solute present in a solution?
Answer:

• Take 100 ml of water in a beaker.
• Take 50 g. of sugar in a plate.
• Add a spoon of sugar to water and stir it tell the sugar dissolve in water.
• Go on adding sugar till you reach a situation that the sugar cannot be dissolved in water.
• Now weigh the sugar remained in the plate.
• Subtract thin weight from 50 g. The weight so obtained is dissolved in water.
• Hence the maximum amount of solute present in 100 ml of solvent is the percentage of solute (solubility).

9th Class Physical Science Textbook Page No. 44

Question 6.
Did you ever observe this phenomenon in the cinema halls?
Answer:
In cinema halls when we observe the projector while the movie is running, we can observe the phenomenon of “Tyndall effect”. We can see the beams of light in which dust particles also observed.

9th Class Physical Science Textbook Page No. 46

Question 7.
Is the mixture heterogeneous? Give reasons.
Answer:
The mixture of ammonium chloride and salt is a heterogeneous mixture. Even though these two are white in colour their particles do not mix.

Question 8.
How do we separate the salt and ammonium chloride?
Answer:
We can separate the salt and ammonium chloride by the method of sublimation.

9th Class Physical Science Textbook Page No. 49

Question 9.
Can you give any examples where we use fractional distillation technique?
Answer:
We use this technique in separating the components of crude oil i.e., petrol, naphthalene, kerosene, greese, etc.

9th Class Physical Science Textbook Page No. 38

Question 10.
How does a laundry dryer squeeze out water from wet clothes?
Answer:

• The laundry dryer contains a cylindrical vessel with holes on its walls.
• When wet clothes are dropped in it, it is rotated with high speed with the help of an electric motor.
• Due to centrifugation, the water from the clothes reaches to the walls of the cylinder and comes out through the holes.
• Hence the clothes are dried up.

9th Class Physical Science Textbook Page No. 40

Question 11.
a) “All the solutions are mixtures, but not all mixtures are solutions”. Discuss about the validity of the statement and give reasons to support your argument.
Answer:

• You take any solution like salt solution, sugar solution, air, etc. all are homogeneous mixtures.
• Consider a mixture of sand and iron fehlings. It is not homogeneous. Hence this is not a solution.

b) Usually we think of a solution as a liquid that contains either a solid, liquid or a gas dissolved in it. But, we can have solid solutions. Can you give some examples?
Answer:
Examples of solid solutions are :

1. Steel used in constructions (a homogeneous mixture of iron and carbon).
2. Brass (a homogeneous mixture of zinc and copper).

9th Class Physical Science Textbook Page No. 43

Question 12.
1) Have you ever observed carefully the syrup that you take for cough? Why do you shake it before consuming?
2) Is it a suspension or colloidal solution?
Answer:

1. The syrup used for cough will be shook before consuming because it consists some undissolved particles settled down.
2. Hence cough syrup is a suspension.

9th Class Physical Science Textbook Page No. 45

Question 13.
Is there any difference between a true solution and colloidal solution? If you find the differences, what are those differences?
Answer:
Differences between true solutions and colloidal solutions :

Question 14.
Why do we use different separation techniques for mixtures like grain and husk as well as ammonium chloride and salt though both of them are heterogeneous mixtures? What is the basis for choosing a separation technique to separate mixtures?
Answer:
The basis for choosing a separation technique to separate mixtures is the property of a component in the mixture i.e., solubility in water, evaporation, appearance, etc.

9th Class Physical Science Textbook Page No. 47

Question 15.
Is it possible to find out adulteration of kerosene in petrol with this technique?
Answer:
The adulteration of kerosene in petrol can be found by using density meter.

9th Class Physical Science Textbook Page No. 50

Question 16.
a) Arrange the gases present in air in increas you observe?
Answer:

b) Which gas forms the liquid first as the air is cooled?
Answer:
Oxygen forms the liquid first as the air is cooled.

9th Class Physical Science 3rd Lesson Is Matter Pure? Activities

Activity – 1

Question 1.
How can we separate cream from milk?
Answer:

• Take some milk in a vessel.
• Spin it with a milk churner for some time.
• After some time you observe, separation of a paste like solid out of the milk.
• The paste like solid is called cream.

Activity – 2

Question 2.
Explain a demonstration to identify homogeneous and heterogeneous mixtures.
Answer:

• Take two test tubes.
• Now add one tea spoon of salt to both the test tubes.
• Fill one test tube with water and another with kerosene and stir them.
• In the first test tube (water), the salt dissolves completely.
• This is a homogeneous mixture.
• In the second test tube (kerosene), the salt is not dissolved.
• This is a heterogeneous mixture.

Activity – 3

Question 3.
Describe an activity to prepare saturated and unsaturated solutions.
Answer:
Preparation of saturated solution :

1. When no more solute can be dissolved in the solution at a certain temperature, it is said to be a saturated solution.
2. Take 50 ml of water in an empty cup.
3. Add one spoon of sugar to the water in the cup.
4. Stir the water until it dissolves.
5. Keep on adding sugar to the cup and stir till no more sugar can be dissolved in it.
6. Thus formed solution is called saturated solution.
7. In a saturated solution, equilibrium with the undissolved solute at a certain temperature.

Preparation of unsaturated solution :

1. If the amount of solute present in a solution is less than that in the saturated solution, is called an unsaturated solution.
2. Now take the solution prepared by you into a beaker.
3. Heat that solution slowly by 5 to 6°C above the room temperature.
4. The undissolved solute dissolves.
5. Add some more sugar to this solution.
6. You notice that more sugar dissolves in it easily when it is heated.
7. Thus we prepared an unsaturated solution.

Activity – 4

Question 4.
What are the factors affecting the rate of dissolving ? How do you prove them?
Answer:
Factors affecting the rate of dissolving are :

1. Temperature of the solvent.
2. Size of the solute particles.
3. Stirring the solution.

Proof:

1. Take three glass beakers and fill each of them with 100 ml of water.
2. Add two spoons of salt to each beaker.
3. Place the first beaker undisturbed.
4. Stir the contents of the second beaker.
5. Heat gently the third beaker.
6. In all the cases, the salt dissolves but the time taken to dissolve is different.
7. When the beaker is heated, the salt dissolved quickly.
8. When we stir the contents, the salt dissolved but slower than heating.
9. When we observe the undisturbed beaker, the salt dissolves but at the slowest rate.
10. This shows that the temperature of the solvent, size of the solute particles, stirring of contents are the factors affecting the rate of dissolving.

Activity – 5

Question 5.
Describe an experiment to identify suspensions and colloids.
Answer:

• Take some chalk powder in a test tube.
• Take a few drops of milk in another test tube.
• Add water to these samples and stir with a glass rod.
• Now do the following steps and write your observations in the table given.

Step 1 :
Direct a beam of light from a torch or a laser beam on the test tubes. Observe the path of the light through the solutions.

Step 2 :
1) Leave the mixture undisturbed for some time.
2) See whether the solute settles down after some time.

Step 3 :
Filter the mixtures and observe any residue found on the filter paper.
Now read your observations :

Observations :

1. In the chalk mixture, the particles of chalk settled at the bottom of the test tube and on filtration, we can observe a residue on the filter paper.
2. Hence the chalk mixture is a suspension.
3. In the milk mixture, the particles of milk are uniformly spread throughout the mixture and no residue is found on the filter paper.
4. Hence milk mixture is a colloidal solution.

Activity – 6

Question 6.
Describe an example for the separation of mixtures by sublimation.
Describe a method of separating ammonium chloride from the mixture of ammonium chloride and common salt.
Answer:
Aim :
To separate ammonium chlo-ride from the mixture of ammonium chloride and common salt.

Materials required :
China dish, funnel, cotton, ammonium chloride, common salt and stove.

Procedure:

1. Take one table spoon of ammo-nium chloride and one table spoon of common salt and mix them.
2. Take the mixture in a China dish.
3. Take a glass funnel.
4. Plug the mouth of the funnel with cotton.
5. Invert the funnel over the dish.
6. Heat the dish on the stove and observe the walls of the funnel.

Observations :
Initially we find vapours of ammonium chloride and then solidified ammonium chloride on the walls of the funnel.

Activity – 7

Question 7.
Describe a method to separate the dye present in ink.
(or)
Describe an example for the separation of a mixture by the process of evaporation.
Answer:
Aim :
To separate the dye present in ink by the process of evaporation.

Materials required :
Beaker, watch glass, water, ink and stove.

Procedure :

1. Take a beaker and fill it to half its volume with water.
2. Keep 3, glass on the mouth of a beaker.
3. Put few drops of ink on the watch glass.
4. Heat the beaker and observe the watch glass.

Observations:

1. We observe some fumes coming from the watch glass.
2. Continue heating till you do not observe any further change on the watch glass.
3. A small residue will be remained on the watch glass.

Inference :

1. We know that ink is a mixture of a dye in water.
2. The residue remained on the watch glass is the dye present in the ink.

Lab Activity

Question 8.
Describe paper chromatography activity to observe the colours present in a marker ink.
(OR)
How can you perform chromatography activity in your laboratory.
Answer:
Aim :
Separating the components of ink using paper chromatography.

Materials required :
Beaker, rectangular shaped filter papers, black marker (non-permanent), water, pencil and cello tape.

Procedure:

1. Draw a thick line just above the bottom of the filter paper using the marker.
2. Pour some water into the beaker.
3. Hang the paper strip with help of a pencil and tape in such a way that it should just touch the surface of water.
4. Make sure that the ink line or mark does not touch the water.
5. Allow the water to move up the paper for 5 minutes and then remove the strip from water.
6. Let it dry.
7. Repeat the process with green marker, a permanent marker, etc.

Observations :

1. When black marker is used, we observe different colours like red, green, violet, black, etc. on the filter paper after drying.
2. When green marker is used, we observe yellow, blue, green colours on the filter paper.
3. When permanent marker is used, we cannot find any change in the mark.

Activity – 8

Question 9.
How do you separate water and kerosene from the mixture of kerosene and water?
Answer:
Aim :
To separate water and kerosene from the mixture of kerosene and water.

Materials required :
Kerosene, water, separating funnel, beakers.

Procedure:

1. Pour the mixture of kerosene and water in a separating funnel.
2. Let it stand undisturbed for some time, so that the layers of oil and water are formed.
3. Open the stopcock of the separating funnel and pour out the lower layer of water carefully.
4. Close the stopcock of the separating funnel as the oil reaches the stop cock.

Principle involved :
The immiscible liquids separate out into layers depending on their densities.

Activity – 9

Question 10.
Explain the method of separation of two miscible liquids by distillation.
Answer:
Aim :
To separate two miscible liquids (water and acetone) by distillation.

Materials required :
Stand, distillation flask, thermometer, condenser, beaker, acetone and water, one holed rubber cork.

Procedure:

1. Take a mixture of acetone and water in a distillation flask.
2. Fit it with a thermometer and clamp it to stand.
3. Attach the condenser of the flask on one side.
4. On the other side of the condenser keep a beaker to collect distillate.
5. Heat the mixture slowly.
6. Keep a close watch on the thermometer.
7. The acetone vapourizes and condenses in the condenser.
8. The acetone can be collected from the condenser outlet.
9. Water remains in the distillation flask.
10. The separation technique used above is called distillation.

Activity – 10

Question 11.
How do you separate copper metal from the mixture of copper sulphate and aluminium?
Answer:

• Take a concentrated solution of copper sulphate into a beaker.
• Drop an aluminium foil in the beaker.
• After some time, we observe a layer of copper deposited on the aluminium foil.
• The solution becomes colourless.
• A chemical reaction takes place among the copper ions present in the solution with aluminium and copper metal is separated.

AP State Syllabus AP Board 9th Class Social Studies Important Questions Chapter 6 Agriculture in India.

AP State Syllabus 9th Class Social Studies Important Questions 6th Lesson Agriculture in India

9th Class Social 6th Lesson Agriculture in India 1 Mark Important Questions and Answers

Question 1.
Expand MSP. (SA-II : 2016-17)
Answer:
Minimum Support Price

Question 2.
Draw sketch map of India and identify paddy cultivating state. (SA-II : 2016-17)
Asnwer:

Question 3.
Why is a MSP needed? (SA-II : 2017-18)
Answer:
The government sets the MSP so as to cover the cost of cultivation and allow a little bit of profit to the farmer.

Question 4.

Study the map and answer the following question. (SA-I : 2018-19)
What is major crop in the shaded areas of the map?
Answer:
Paddy.

Question 5.
Name any two cropping seasons in India? (SA-I : 2018-19)
Answer:
Kharif, Rabi, Zaid are the three cropping seasons.

9th Class Social 6th Lesson Agriculture in India 2 Marks Important Questions and Answers

Question 1.
At present we are using under ground water heavily and they reached an endangered stage, indicate measures to restore the ground water. (SA-III : 2015-16)
Answer:
The following steps are the measures to restore ground water.

• Vegetation like trees and grasses and bonds are used to enhance ground water.
• We follow watershed development projects.
• Rainwater harvesting should be practiced.
• Reduce the wastage of water.

Question 2.
Observe the Bar graphs and write your observations. (SA-II : 2016-17)

Answer:

• Above Bar graph tells us how many cultivators and how many agricultural labourers are there in India.
• Years are passing away gradually percentage of cultivators is decreasing and the persons, who are agricultural labourers are increasing

Question 3.
Show the below information on a bar graph and based on this, write your observation. (SA-III : 2016-17)

Answer:

The above graph explains production of food grains is gradually increased from 1980-81 to 2010-11. The main reason is we are following green revolution methods in our agricultural iands.

Question 4.
Today food materials constitute only about three percent of Indian Imports. Explain the role of Green Revolution that lies behind this achievement. (SA-III : 2016-17)
Answer:
The production of food grains has increased five times over last five decades from 51 to 242 million tonnes.

The green revolution helped farmers to produce higher level of foodgrains and non- foodgrains on the same plot of land they had. There was no major increase in the land used for cultivation.

In 1960s a farmer was able to produce on an average only 287 kilograms of foodgrains be it paddy or wheat on one acre of cultivable land. Today the same farmer is able to produce nearly 800 kilograms of foodgrains per acre of cultivable land.

Importance of Green Revolution :

1. Using of highyielding varieties of seeds.
2. Using of pesticides and insecticides.
3. Providing better water management resources.

Question 5.
Write the names of cropping seasons in India and write the tenure of season. (SA-II : 2017-18)
There are three cropping seasons.

9th Class Social 6th Lesson Agriculture in India 4 Marks Important Questions and Answers

Question 1.
“The green revolution has resulted in a loss of soil fertility and ever increasing costs to farmers”. Do you agree with this statement? Explain. (SA-I : 2018-19)
(OR)
“The green revolution has actually resulted in a loss of soil fertility and ever increasing cost to the farmers’ (SA-II : 2018-19)
Do you agree with the above statement? Provides reasons to support your answer.
Answer:
Yes, I agree with the above statement by following reasons.

1. In Green Revolution, the farmers are encouraged to pump ground water to water intensive crops in low rainfall areas.
2. This unsustainable pumping has reduced water storage in ground.
3. Consequently, many wells and tube wells have run dry.
4. More over the use of chemical fertilizers has also affected the long term fertility of the soil. Due to this cost of production is increasing to farmers.
5. Hence we can say that Green Revolution has short-term gains and long term losses.
6. Production of food grains (in million tonnes)

Question 2.

Observe the above graph and answer the following questions.
1. What does the graph given above denotes? (SA-III : 2015-16)
Answer:
The above graph explains the production of foodgrains from 1950-51 to 2010-11 years.

2. When compared to 1970-71, how many million tonnes of food grains are produced more in 2010-11? (SA-III : 2015-16)
Answer:
Compare with 1970-71 to 2010-11 the food grain production is increased from 108 million tonnes to 242 million tonnes, it means ⇔ 134 million tonnes production is more.

3. In which decade was the production of food grains more? (SA-III : 2015-16)
Answer:
From 1981 to 1990 in the middle of the years means, in this decade the production of food grains is more.

4. What are the reasons for the increase in production of food grains? (SA-III : 2015-16)
Answer:
The main reason is use of Green Revolution methods.

5. What is the overall trend of food grain production depicted in the graph? (SA-I : 2019-20)
Answer:
Food grain production is increasing.

6. What could be the possible reason for this trend? (SA-I : 2019-20)
Answer:
Because of Green Revolution.

Question 3.
“Conserving rainfall that the area receives is the first step. There are several ways that people can stop rainwater from quickly running off so that it can soak into the ground, and recharge the groundwater”.
Q : Comment on watershed development programms being implemented in dry land area. (SA-II : 2016-17)
Answer:
Unlike the cultivation of HYVs in irrigated lands, dryland farming possess different challenges.

1. Conserving rainfall that the area receives is the first step.
2. There are several ways that people can stop rain water from quickly running off, so that it can soak into the ground, and recharge the ground water.

This is done through Watershed Development Programmes which include afforestation, bunding, building check dams and tanks.

Not send any chemical waste into underground.

Try to reduce the wastage of daily use water.

Create awareness among the all people about the importance of underground water and its recharge.

Question 4.
Food security of a nation depends on agricultural sector. Explain about agricultural sector in India. (SA-III : 2016-17)
Answer:
The food security of a nation depends on agriculture and this sector ensures food security to the nation.

Importance of agriculture :

• A variety of raw materials required for industries are cultivated on farms.
• Agriculture is a major source of livelihood for millions – giving employment to a large section of people.
• More than half the proportion of workers in India is working in agriculture and its related activities.
• 70% of working women are engaged in agriculture.
• Due to green revolution, India became self sufficient in food grains.
• Due to rise in food grains production, it was no longer necessary to import food grains from other countries.

Question 5.
Study the graph and answer the questions given below. (SA-II : 2018-19)

1. What is the difference between agriculture labourers and cultivators?
2. In 1971, what was the percentage of cultivators?
3. Suggest other alternative job opportunities for landless agriculture labourers,
4. In which year the highest percentage of cultivators was recorded?
Answer:
1. Cultivator means:
Cultivators are those who have, some land and also use land belongs to other for cultivation.

Agricultural labourers :
Agriculture labourers are those who are landless labourers who work on other lands.

2. 62%

3. Other alternative works.

1. rearing of animals
2. selling of vegetables
3. work in brick kiln.

4. 1961

Question 6.
What suggestions do you recommend to solve the problems associated with current Indian agriculture sector? (SA-I : 2018-19)
Answer:
Suggestions :
1. Better irrigation facilities :
Indian agriculture is mainly dependent on monsoon. So permanent means of irrigation should be developed.
Ex: Tube wells & Canals.

2. Supply of Quality seeds :

1. Quality seeds should be sold through co-operative societies or village panchayats.
2. Marginal farmers should be given seeds on loan.

3. Green Manure :
Farmers should be educated for firing green manure. Oil cakes may be used as fertilizers.

4. Credit Facilitied :

1. Farmers should be advanced loans at reasonable rates of interest.
2. Regional Rural Banks should be opened.

5. Agricultural Marketing:
Agricultural marketing should be improved so that the farmer gets proper price for their produce ware housing facilities should be improved. Means of transport should be strengthened.

6. Time to time weather reports telecast by govt through media.

Question 7.
Observe the table and answer the questions given below. (SA-I : 2018-19)
Number of farmers and land they possess in India (2010 – 2011)

1. Who are considered as large farmers as per the above table?
2. Which type of farmers are high in number?
3. How many total acres of land do the farmers cultivate in India?
4. How much of land on an average does each marginal farmer cultivate?
Answer:

1. The farmers who have more than 25 acres of land and they cultivated that land are called as large farmers.
2. Number of marginal farmers are more.
3. 3932 lakhs acres of land cultivated by Indian farmers.
4. 0.95 acres of land is cultivated by marginal farmers.

Question 8.
Write some methods through which the problem of falling ground water levels can be salved. (SA-I : 2019-20)
Answer:
The problem of falling ground water levels can be solved through these methods.

1. Construction of check dams.
2. By Maintaining small percolation tanks in fields.
3. Soaking pits.
4. By providing bunds and catch drains.
5. Plantation of trees in open fields.
6. Encouragement to grow forests.
7. Should ban felling trees.
8. Recycle and reuse of ground water.

9th Class Social 6th Lesson Agriculture in India Important Questions and Answers

Question 1.
Name one staple crop of India and the regions where it is produced.
Answer:
Rice:

1. Rice is the staple food crop of a majority of the people in India.
2. India is the second largest producer of rice in the world.
3. Rice is grown in the plains of north and north-eastern India, coastal areas and the deltaic regions.
4. Canal irrigation and tubewells have made it possible to grow rice in areas of less rainfall such as Punjab, Haryana and western Uttar Pradesh and parts of Rajasthan.

Question 2.
How many cropping seasons are there? What are they?
Answer:
India has three cropping seasons. They are –

1. Rabi
2. Kharif
3. Zaid

Question 3.
Name some important crops of India, states which produce them and reasons both and natural and other factors contributed to their growth.
Answer:

Question 4.
What is the fertility of the soil?
Answer:

• The soil is said to be fertile if it has the right amounts of mineral particles as well as organic components.
• Then only the soil can provide the roots of plants with right amounts of water, minerals and air.

Question 5.
How is organic farming different from traditional farming?
Answer:

• We use organic material in organic farming whereas we use natural manure in traditional farming.
• We use HYV seeds and key elements of new agricultural technologies in organic farming.
• Organic farming gives high productivity in short duration whereas in traditional farming we experience less productivity and long duration of crop.

Question 6.
Why is agriculture important to Indian economy?
Answer:

• The food security of a nation depends on agriculture.
• A variety of raw materials required for industries are cultivated on farms.
• Agriculture is a major source of livelihood for millions of people in our country.
• More than half the proportion of workers in India is working in agriculture and its related activities.
• Nearly 70% of the working women are engaged in agriculture.

Hence agriculture is important to Indian economy.

Question 7.
How many kinds of people are engaged in agriculture? Name them.
Answer:
Two kinds of people are engaged in farming. They are :

1. Agricultural labourers
2. Cultivators.

Question 8.
Distinguish between cultivators and agricultural labourers.
Answer:

Question 9.
How many varieties of crops are grown in India? What are they?
Answer:
A variety of crops are cultivated by farmers in India. They are broadly categorised into two :

1. Food crops
2. Non-food crops.

Question 10.
Give examples of food grains and non-food grains.
Answer:

• Food grains include cereals such as rice, wheat, jowar, bajra, maize, ragi, barley, and small millets and pulses-gram, red gram, and other pulses.
• Non-food grains include oilseeds such as groundnut, sesame, rapeseed and mustard, linseed, castor seed, and sunflower, etc.

Question 11.
What is Green Revolution? What are the effects of Green Revolution?
Answer:

• The policy introduced by Government with regard to the agricultural sector is known as Green Revolutin.
• It refers to the specific plant improvement notably to the development of high yielding varieties for the increase of crop production.

Effects of Green Revolution:

1. The spread of HYVs to large parts of the country has led to a significant increase in crop production in the country.
2. So, it was no longer necessary to import food grains from other countries.
3. The procurement of food grains by FCI could be used in case of shortage and can avoid drought or famine like situations and also used to supply food grains to inaccessible areas.
4. In 1960, a farmer was able to produce on an average of 287 kgs of foodgrains, today the same farmer is able to produce nearly 800 kgs of food grains per acre.
5. The Green Revolution has brought in several environmental imbalances.

Question 12.
Name some of the states of India where “slash and burning” farming is practised.
Answer:
Punjab, Haryana, Odisha, Karnataka, Telangana, Andhra Pradesh, Madhya Pradesh, Uttar Pradesh, and some parts of Rajasthan.

Question 13.
What is the fertility of the soil?
Answer:

1. The soil is said to be fertile if it has the right amounts of mineral particles as well as organic components.
2. Then only the soil can provide the roots of plants with right amounts of water, minerals, and air.

Question 14.
How many kinds of people are engaged in agriculture? Name them.
Answer:
Two kinds of people are engaged in farming. They are :

1. Agricultural labourers
2. Cultivators.

Question 15.
What is Green Revolution?
Answer:
The policy introduced by Government with regard to the agricultural sector is known as Green Revolution.

Question 16.
Compare and contrast simple subsistence farming and intensive subsistence farming.
Answer:

Question 17.
What do you know about Zaid cropping season?
Answer:

• In between the Rabi and Kharif seasons there is a short season.
• It includes summer months and is known as Zaid season.
• Crops grown during this season are like watermelon, muskmelon, cucumber, vegetables and fodder crops.

Question 18.
Read the following and answer the questions given below.

1. What problem do farmers face during harvest season?
Answer:
The farmers face the problem of the low price of grain during harvest season.

2. How can the farmers be protected from the low prices of grains?
Answer:
The government protects the farmers by setting a Minimum Support Price (MSP).

3. What is Minimum Support Price?
Answer:
The MSP is a price at which the farmers can sell their grain, if they want, to the government.

4. How does the MSP protect the farmer?
Answer:
The government sets the MSP so as to cover the cost of cultivation and allow a little bit of profit to the farmer.

5. What is the organization that purchases food grains from the farmers?
Answer:
The Food Corporation India purchases food grains from the farmers.

Question 19.
Observe the following information and answer the questions given below.

1. How many cropping seasons are there?
Answer:
There are three cropping seasons.

2. Name different cropping seasons.
Answer:
Kharif, Rabi and Zaid are different cropping seasons.

3. When do we have Rabi season?
Answer:
Rabi crops are sown in winter from October to December and harvested in summer.

4. Name the crops that are grown in Kharif season.
Answer:
Paddy, maize, jower, bajra, red gram, cotton, jute, groundnut etc., are grown in Kharif season.

5. Name the crops that are grown in Zaid season.
Answer:
Watermelon, muskmelon, cucumber, vegetables are grown in Zaid season.

Question 20.
Complete the data in the table:
Number of farmers and land they possess in India (2010-2011)

A) Percentage of different category of farmers :
1. How much percentage of Marginal farmers are there.
Answer:
67 %

2. How much percentage of small farmers are there?
Answwr:
18 %

3. How much percentage of large farmers are there?
Answer:
0.7 %

B) How much land they operate with?
1) Marginal farmers hold _________ of land.
2) Small farmers hold _________ of land.
3) Semi-medium farmers hold _________ of land.
4) Medium farmers hold _________ of land.
5) Large farmers hold _________ of land.
Answer:

1. 22%
2. 22%
3. 24%
4. 21%
5. 11%

C) Average amount of land operated by farmers :
1) Average amount of land possessed by marginal farmers is _________ acres.
2) Small farmers hold _________ acres of land.
3) Average amount of land possessed by large farmers is _________ acres.
4) Average land holding in India is _________ acres.
Answer:

1. 0.94
2. 3.51
3. 42.9
4. 13.65

Question 21.
What are the long run uses of chemical fertilizers and pesticides?
Answer:

• The chemical fertilizers are basically made from petro chemicals and therefore derived from petroleum.
• These fertilizers remain in the soil and also mix with water.
• This results in the contamination of soil and water.
• As a result many micro organisms like earthworms are destroyed. This in turn affects the long term fertility of the soil.

Question 22.
In which areas were the new methods of agriculture first tried?
Answer:
The new methods were initially implemented in Punjab, Haryana, western Uttar Pradesh, and in some districts of Telangana, Andhra Pradesh, and Tamilnadu.

Question 23.
How were farmers able to raise higher amount of food grains on the same plot of land over the years?
Answer:
The use of High Yielding Varieties of seeds, chemical fertilizers, machinery, etc. made the farmers to raise higher amount of food grains on the same plot of land over the years.

Question 24.
Why did the Indian government not allow farmers to export foodgrains during the Green Revolution?
Answer:
There would be a shortage of food grains if the government allows farmers to export food grains. So the government did not allow farmers to export food grains.

Question 25.
How did the partition of the country in 1947 affect the jute industry?
Answer:
We have lost the major jute growing areas during partition. Hence the jute industry was badly affected.

Question 26.
In your opinion what would be the minimum amount of land required to do viable farming?
Answer:
The minimum amount of land required to do viable farming maybe 2 acres for viable farming.

Question 27.
Why do only a small section of farmers have a powerful voice?
Answer:
Percentage of large and medium farmers is 5% but they hold 32% of total cultivable land. Their average landholding is also high. Hence they have a powerful voice.

Question 28.
Assess the role of monsoons in Indian agriculture nowadays?
Answer:

• Indian agriculture has always been dependent on monsoons.
• Arrival and impact of monsoon decides the fate of agriculture.
• It is both uncertain and irregular.
• The large scale irrigation serves only one third of crop area.
• The remaining has to suffer the vagaries of the monsoon.
• Thus one can term Indian agriculture as ‘a gamble with monsoons.’

Question 29.
How can you say that now India is practising subsistence farming?
Answer:

• India is a densely populated country.
• Farmers here are force to use small land holdings.
• Most farmers produce enough for their own consumption.
• They try to obtain maximum yield from available lands.
• They are artificial irrigation and manure etc.
• This type of farming is known as intensive subsistence farming.
• Thus we can say India is practising subsistence farming.

Question 30.
Do you feel that the farmers who cultivate are happy? If not, what are the reasons? What are the factors that affect agriculture?
Answer:
I feel that the farmers who cultivate are not happy.
Reasons:

1. They are not able to earn according to their labour.
2. They lost their confidence.
3. Nature is also not co-operating with them.

Factors that affect agriculture :

1. Low fertile soils
2. Improper usage of pesticides
3. Small land holdings
4. Unpredictable monsoons
5. Outdated agricultural methods
6. Improper market facilities, etc.

Question 31.
Locate the following on India Map.
Paddy, wheat and maize growing areas.

Answer:
Paddy – West Bengal, Odisha, Telangana, Andhra Pradesh and coastal areas.
Wheat – Punjab, Haryana, Uttar Pradesh
Maize – Karnataka, Telangana, Andhra Pradesh, Maharashtra and Bihar.

Question 32.
Locate the following on India map.
Pulses, sugarcane, cotton growing areas.

Answer:
Pulses – Madhya Pradesh, Maharashtra, Uttar Pradesh, Telangana and Andhra Pradesh.
Cotton – Gujarat, Maharashtra.
Sugarcane – Uttar Pradesh, Maharashtra, Telangana, Andhra Pradesh, Tamilnadu.

Question 32.
Locate the following rivers on the outline map of India.
1) Narmada
2) Tapati
3) Godavari
4) Krishna
5) Cauvery
6) Mahanadi
7) Indus
8) Ganga
Answer:

Question 33.
State your opinion on the new agricultural technologies such as Green Revolution.
Answer:

• Yes, we agree that government has taken initiative in increasing the production of different crops.
• But introduction of HYVs has created some economical imbalances.
• They need plenty of water which may reduce the water levels and at one stage we would face scarcity of water.

Question 34.
State your opinion on free power supply to farmers and the problems that are faced by marginal farmers due to free power supply.
Answer:

• Free power supply to a section of farmers has encouraged them to pump groundwater.
• Consequently, many wells and tubewells have run dry.
• This has pushed the marginal and small farmers out of cultivation.

Question 35.
How did the partition of the country in 1947 affect the Jute industry?
Answer:
We have lost the major jute growing areas during partition. Hence the jute industry was badly affected.

Question 36.
What measures would you suggest to protect agriculture from intense commercial farming?
Answer:

• To protect agriculture from intense commercial farming, we should shun the use of High Yielding Varieties of Seeds.
• Then we can limit the usage of water.
• Then we can limit the usage of chemical fertilisers and pesticides.
• We can save the produce for seeds.
• We can adopt organic farming, which requires very low input costs.
• Organic farm produce also serves health better.

Question 37.
What measures would you suggest for the cultivation of cotton crop?
Answer:

• Cotton grows well in drier parts of the black cotton soil of the Deccan Plateau.
• It requires high temperature, light rainfall or irrigation.
• It needs 210 frost free days and bright sunshine for its growth.
• It requires 6 to 8 months to mature.

AP State Syllabus AP Board 9th Class Physical Science Solutions Chapter 4 Atoms and Molecules Textbook Questions and Answers.

AP State Syllabus 9th Class Physical Science Solutions 4th Lesson Atoms and Molecules

9th Class Physical Science 4th Lesson Atoms and Molecules Textbook Questions and Answers

Improve Your Learning

Question 1.
Draw the diagram to show the experimental setup for the law of conservation of mass. (AS 5)
(OR)
Draw the experimental arrangement used in verifying law of conservation of mass. Write the law of conservation of mass.
Answer:

Question 2.
Explain the process and precautions in verifying law of conservation of mass. (AS 5)
(OR)
Explain the procedure to prove in a chemical reaction the mass neither destroyed.

Answer:
Aim :
To verify law of conservation of mass.

Material required :
Sodium sulphate,Barium chloride, distilled water, conical flask, spring balance, small test tube, rubber cork, thread, retort stand.

Procedure:

1. Prepare a solution of sodium sulphate by dissolving approximately 2 gm of sodium sulphate in 100 ml distilled water in a 250 ml conical flask.
2. Prepare a Barium chloride solution by dissolving approximately 2 gm of potassium iodide in 100 ml water in another conical flask.
3. Take 100 ml solution of sodium sulphate in 250 ml conical flask.
4. Also take 4 ml solution of Barium chloride in test tube.
5. Hang the test tube in the flask carefully without mixing the solutions. Put a cork on the flask.
6. Weigh the flask with its contents carefully by spring balance.
7. Now tilt and swirl the flask, so that the two solutions mix.
8. Weigh the flask again by the spring balance.

Observations:

1. Weight of flask and contents before mixing = m₁ g
2. Weight of flask and contents after mixing = m₂ g

Conclusion :

1. We have observed that the two weights i.e., mj and m2 are equal.
2. This proves the law of conservation of mass.

Precautions:

1. Care should be taken while handling chemicals.
2. Glass apparatus may slip and break down. Hence make sure that they should not slip from your hands.
3. Contents of the conical, ffhsk should not mix before weighing first time.
4. Tie a thick thread to the conical flask, so that it will not slip while weighing.

Question 3.
15.9g of copper sulphate and 10.6g of sodium carbonate react together to give 14.2g of sodium sulphate and 12.3 g of copper carbonate. Which law of chemical combination is obeyed? How? (AS 1, AS 2)
Answer:
Reactants:
Mass of copper sulphate = 15.9 g ; Mass of sodium carbonate = 10.6 g
Total mass of reactants = 15.9 + 10.6 = 26.5 g

Products:
Mass of sodium sulphate = 14.2 g ; Mass of copper carbonate = 12.3 g
Total mass of products = 14.2 + 12.3 = 26.5 g
∴ Total mass of reactants is equal to total mass of products. This is the “Law of conservation of Mass”.

Question 4.
Carbon dioxide is added to 112 g of calcium oxide. The product formed is 200 g of calcium carbonate. Calculate the mass of carbon dioxide used. Which law of chemical combination will govern your answer? (AS 1, AS 2)
Answer:

1. Let x g of carbon dioxide is added to 112 g of calcium oxide.
2. The product is 200 g of calcium carbonate.
3. According to law of conservation of mass, ,
   Total mass of reactants = Total mass of products
   x+ 112 = 200 g
   x = 88 g
   ∴ 88 g of carbon dioxide is used.

Question 5.
0.24 g sample of compound of oxygen and boron was found by analysis to contain 0.144 g of oxygen and 0.096 g of boron. Calculate the percentage composition of the compound by weight. (AS 1)
Mass of compound of oxygen and boron = 0.24 g
On analysis,
Mass of oxygen in the compound = 1.44 g
Mass of boron in the compound = 0.096 g

Question 6.
In a class, a teacher asked students to write the molecular formula of oxygen. Shamita wrote the formula as 02 and Priyanka as O. Which one is correct? State the reason. (AS 1, AS 2)
Answer:
Shamitha’s answer is correct.
Reason :

1. Oxygen is diatomic.
2. Two atoms of oxygen combine to form oxygen molecule.
3. Hence the formula of oxygen molecule will be ‘O₂‘.

Question 7.
Imagine what would happen if we do not have standard symbols for elements. (AS 2)
(OR)
Is it necessary to use symbols for elements? Write your opinion.
Answer:

• Chemistry involves a lot of reactions.
• If we do not have symbols, we have to write their names to represent the reactions.
• This is very tedious work.
• To avoid this, we need standard symbols to elements, which are universally accepted.
• In advanced studies, balancing of equations, atoms present in a compound, etc. will not be understood without symbols.
• Simply chemistry will not be developed unless symbols, formulae, etc. are not known.

Question 8.
Mohith said “H₂ differs from 2H.” Justify. (AS 1)
Answer:
H₂ is the hydrogen molecule in which two hydrogen atoms are combined to form one hydrogen molecule.

2H is the hydrogen atom. Here 2 hydrogen atoms are ready to participate in chemical reaction.

Question 9.
Lakshmi gives a statement “CO and Co both represent element”. Is it correct? State reason. (AS 1, AS 2)
Answer:
Lakshmi’s statement is incorrect.

Reason :

1. CO stands for carbon monoxide, a compound, which consists carbon and oxygen atoms.
2. This can be identified with the help of both C and O are capital (upper case) letters.
3. Co stands for cobalt, an element.
4. This can be identified with the help of ‘C’ is capital (upper case) letter and ‘o’ small (lower case) letter.

Question 10.
The formula of water molecule is H₂O. What information do you get from this formula? (AS 1)
Answer:

• Water is a combination of hydrogen and oxygen.
• Two hydrogen atoms and one oxygen atom combine to form one water molecule.
• Molecular weight of water molecule is 18. [Hydrogen 1, Oxygen 16. H₂O ⇒ 2 × 1 + 16=18]
• 18 g of water molecule contains 6.022 × 10²³ particles in it.
• Valency of hydrogen is 1 and oxygen is 2.

Question 11.
How would you write 2 molecules of Oxygen and 5 molecules of Nitrogen? (AS 1)
Answer:
2 molecules of oxygen → 2O₂
Reason :

1. Oxygen is diatomic element.
2. Two oxygen atoms combine to form one oxygen molecule.
3. The formula of oxygen molecule is O₂.

5 molecules of nitrogen → 5N₂
Reason :

1. Nitrogen is also diatomic element.
2. Two nitrogen atoms combine to form one nitrogen molecule.
3. Molecular formula of nitrogen is N₂.

Question 12.
The formula of a metal oxide is MO. Then write the formula of its chloride. (AS 1)
Answer:

• The valency of oxide is 2 i.e., O^-2.
• The formula of a metal oxide is given as MO.
• Hence the valency of the given metal must be 2 i.e., M⁺².
• Valency of chloride is 1 i.e., C^–.
• Therefore according to criss-cross method, the formula of given metal chloride will be MCl₂.

Question 13.
Formula of calcium hydroxide is Ca(OH)₂ and zinc phosphate is Zn₃(PO₄)₂. Then write the formula to calcium phosphate. (AS 1)
(OR)
Formula of calcium hydroxide is Ca(OH)₂ and zinc phosphate is Zn₃(PO₄)₂. Then write the valencies of calcium and phosphate and then write the formula of calcium phosphate.
Answer:

• Formula of calcium hydroxide is Ca(OH)₂.
• From criss-cross method we know that the valency of calcium is 2 i.e., Ca⁺² and hydroxide is 1 i.e., OH^–.
• Formula of zinc phosphate is Zn₃(PO₄)₂.
• Valency of Zn is 2 i.e., Zn^+2, and valency of phosphate is 3 i.e., PO₄^-3.
• Now the formula of calcium phosphate according to criss-cross method is Ca₃(PO₄)₂.

Question 14.
Find out the chemical names and formulae for the following common household substances. (AS 1)
a) Common salt
b) Baking soda
c) Washing soda
d) Vinegar
Answer:

Question 15.
Calculate the mass of the following. (AS 1)
a) 0.5 mole of N₂ gas
b) 0.5 mole of N atoms
c) 3.011 × 10²³ number of N atoms
d) 6.022 × 10²³ number of N₂ molecules
Answer:
a) 0.5 mole of N₂ gas :
Mass of one mole of N₂ gas = 28 g. (∵ Molecular wt. of N₂ = 28)
Mass of 0.5 mole of N₂ gas = 28 × 0.5 = 14 g

b) 0.5 mole of N atoms :
Mass of one mole of N atoms = 14 g (∵ Atomic wt. of N = 14)
Mass of 0.5 mole of N atoms = 14 × 0.5 = 7 g

c) 3.011 × 10²³ number of N atoms :
Mass of 6.022 × 10²³ number of N atoms = 14 g

d) 6.022 × 10²³ number of N₂ molecules :
Mass of 6.022 × 10²³ number of N₂ molecules = 28 g

Question 16.
Calculate the number of particles in each of the following. (AS 1)
a) 46 g of Na
b) 8 g of O₂
c) 0.1 mole of hydrogen
Answer:
a) 46 g of Na :
Atomic weight of Na = 23
Number of particles in 23 g of Na atom = 6.022 × 10²³

b) 8 g of O₂ :
Molecular weight of O₂ is 32.
Number of particles in 32 g of O₂ molecule = 6.022 × 10²³

c) 0.1 mole of hydrogen :
Atomic weight of hydrogen is 1.
Number of particles in 1 mole of hydrogen = 6.022 × 10²³
Number of particles in 0.1 mole of hydrogen= \(\frac{0.1}{1}\) × 6.022 × 10²³ = 6.022 × 10²²

Question 17.
Convert into moles. (AS 1)
a) 12 g of O₂ gas
b) 20 g of water
c) 22 g of carbon dioxide
Answer:
a) 12 g of O₂ gas :
Molecular weight of O₂ is 32.
∴ Number of moles of 32 g of O₂ gas = 1

b) 20 g of water :
Molecular weight of water (H₂O) is 18.
Number of moles of 18 g of water = 1
Number of moles of 20 g of water = \(\frac{20}{18}\) x 1 =1.11

c) 22 g of carbon dioxide :
Molecular weight of carbon dioxide (CO₂) is 44.
∴ Number of moles of 44 g of CO₂ = 1

Question 18.
Write the valencies of Fe in FeCl₂ and FeCl₃. (AS 1)
Answer:

1. In FeCl₂, the valency of Fe is 2.
2. In FeCl₃, the valency of Fe is 3.

Question 19.
Calculate the molar mass of sulphuric acid (H₂SO₄) and glucose (C₆H₁₂O₆). (AS 1)
Answer:
a) Formula of sulphuric acid is H₂SO₄.
Molecular mass of H₂SO₄ = 2 × 1 + 1 × 32 + 4 × 16 = 2 + 32 + 64 = 98 u
∴ Molar mass of H₂SO₄ = 98 g

b) Formula of glucose is C₆H₁₂O₆.
Molecular mass of C₆H₁₂O₆ = (6 × 12) + (12 × 1) + (6 × 16) = 72 + 12 + 96 = 180 u
∴ Molar mass of C₆H₁₂O₆ = 180 g.

Question 20.
Which has more number of atoms – 100 g of sodium or 100 g of iron? Justify your answer. (Atomic mass of sodium = 23 u, atomic mass of iron = 56 u) (AS 1)
Answer:
100g of sodium has more number of atoms than 100g of iron.

Justification :
1) Atomic mass of sodium = 23 u
23 g of sodium contains 6.022 × 10²³ atoms.
100 g of sodium contains = \(\frac{100}{23}\) × 6.022 × 10²³ = 26.1826 × 10²³ atoms of sodium.

2) Atomic mass of iron = 56 u
∴ 56 g of iron contains 6.022 × 10²³ atoms.
100 g of iron contains = \(\frac{100}{56}\) × 6.022 × 10²³ = 10.7535 × 10²³ atoms of iron.

Question 21.
Complete the following table. (AS 1)

Answer:

Question 22.
Fill the following table. (AS 1)

Answer:

Question 23.
Make placards with symbols and valencies of the atoms of the elements separately. Each student should hold two placards, one with the symbol in the right hand and the other with the valency in the left hand. Keeping the symbols in place, students should criss-cross their valencies to form the formula of a compound.
Answer:
Student’s activity.

Question 24.
Take empty blister packs of medicines. Cut them into pieces having

Hence the formula of sodium carbonate will be Na₂ CO₃
Hence the forrnu A. Student’s activity.

9th Class Physical Science 4th Lesson Atoms and Molecules InText Questions and Answers

9th Class Physical Science Textbook Page No. 56

Question 1.
Does the weight of iron rod increase or decrease, on rusting?
Answer:
The weight of iron rod decreases on rusting.

Question 2.
Where does the matter charcoal go?
Answer:
The charcoal, on burning, gives off CO₂ which is mixed in atmosphere. The residue is remained as ash.

Question 3.
Wet clothes dry after some time – where does the water go?
Answer:
Water evaporates and mixed in the atmosphere.

Question 4.
What happens to magnesium on burning it in air?
Answer:
Magnesium on burning in air gives a bright light and ash is remained. The ash is magnesium oxide.

Question 5.
What happens to sulphur on burning it in air?
Answer:
Sulphur on burning, changes its state and colour.

9th Class Physical Science Textbook Page No. 57

Question 6.
Did you observe any precipitate in the reaction?
Answer:
In the flask, a reaction takes place between lead nitrate and potassium iodide.

Question 7.
Do you think that a chemical reaction has taken place in the flask? Give reason.
Answer:
Yes, the contents in the flask are changed as lead iodide and potassium nitrate.

9th Class Physical Science Textbook Page No. 58

Question 8.
Do the weights of the flask and its contents change during the activity?
Answer:
The weights of the flask and its contents do not change before and after reaction.

Question 9.
What are your conclusions?
Answer:
Mass was neither created nor destroyed.

Question 10.
What do you observe from table – 1?
Answer:
The components of a compound are mixed at same proportions in any sample.

9th Class Physical Science Textbook Page No. 59

Question 11.
What difference do you observe in percentage of copper, carbon, and oxygen in two samples?
Answer:
The percentage of copper, carbon and oxygen are same in two samples, i.e., they are mixed at same proportions.

9th Class Physical Science Textbook Page No. 60

Question 12.
Are elements also made of atoms?
Answer:
When the particles of a substance contain only one type of atoms, that substance is called an element. In elements the smallest particle that exist may be atoms or molecules.

9th Class Physical Science Textbook Page No. 62

Question 13.
How do we write the symbols for calcium, chlorine, chromium?
Answer:
We have only 26 alphabets in English, but there are over 100 known elements. We cannot write the same symbol for carbon, calcium, chromium, etc.

9th Class Physical Science Textbook Page No. 63

Question 14.
Would you be able to recognise the elements of the table – 2, have symbols of this category?
Answer:
Yes. They are iron, gold, sodium, and potassium.

9th Class Physical Science Textbook Page No. 64

Question 15.
Observe the atomicity and fill the following table.

Answer:

Question 16.
What is valency?
Answer:
Every element reacts with other element according to its combining capacity, which we call as its valency.

9th Class Physical Science Textbook Page No. 66

Question 17.
Can you write the formula of carbon dioxide and carbon monoxide? Try to write formula for them as we have done in case of water molecule.
Answer:
Carbon dioxide :
The elements present are carbon and oxygen. One atom of carbon and one atom of oxygen are present in a molecule of carbon monoxide. Hence the formula of carbon monoxide is CO.

Carbon dioxide :
The elements present are carbon and oxygen. One atom of carbon and 2 atoms of oxygen are present in a molecule of carbon dioxide. Hence the formula of carbon dioxide is CO₂.

9th Class Physical Science Textbook Page No. 69

Question 18.
How many molecules are there in 18 grams of water?
Answer:
6.022 × 10²³ molecules are there in 18 grams of water.

Question 19.
How many atoms are there in 12 grams of carbon?
Answer:
6.022 × 10²³ atoms are there in 12 grams of carbon.

9th Class Physical Science Textbook Page No. 58

Question 20.
Do you get the same result if the conical flask is not closed?
Answer:

1. No, we cannot get the same result.
2. When the conical flask is not closed, some gases will leave out the flask during chemical reaction.

Question 21.
Recall the burning of the magnesium ribbon in air. Do you think mass is conserved during this reaction?
Answer:

1. Yes, but we cannot observe the conservation of mass.
2. When the experiment is conducted in a closed container where there is no scope for oxygen to escape, we can observe the conservation of mass. But in this condition this experiment is not possible.

9th Class Physical Science Textbook Page No. 59

Question 22.
100 g of mercuric oxide decompose to give 92.6 g of mercury and 7.4 g of oxygen. Let us assume that 10 g of oxygen reacts completely with 125 g of mercury to give mercuric oxide. Do these values agree with the law of constant proportions?
Answer:
Proportion of oxygen = 7.4 : 10
Proportion of mercury = 92.6 : 125
\(\Rightarrow \frac{7.4}{10}=\frac{92.6}{125} \Rightarrow 0.74=0.74\)
∴ They follow law of constant proportions.

Question 23.
Discuss with your friends if the carbon dioxide that you breathe out and the carbon dioxide they breathe out are identical. Is the composition of the carbon dioxide of different sources same? (Page – 73)
Answer:
Same.
This can be justified with the help of law of constant proportions.

9th Class Physical Science Textbook Page No. 60

Question 24.
Which postulate of Dalton’s theory is the result of the law of conservation of mass?
Answer:
First postulate of Dalton’s theory i.e. “Matter consists of indivisible particles called atoms”, is the result of law of conservation of mass.

Question 25.
Which postulate of Dalton’s theory can explain the law of constant proportions?
Answer:
Third postulate of Dalton’s theory i.e. “Atoms of a given element have identical mass and chemical properties. Atoms of different elements have different masses and chemical properties”, is the result of law of constant proportions.

9th Class Physical Science 4th Lesson Atoms and Molecules Activities

Activity – 1

Question 1.
Some elements and their possible symbols are given. Correct them and give reasons for your corrections.
Answer:

Activity – 2

Question 2.
Write the symbols for given elements.

Answer: