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Practice the AP 9th Class Physical Science Bits with Answers Chapter 6 Chemical Reactions and Equations on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 9th Class Physical Science Bits 6th Lesson Chemical Reactions and Equations with Answers

Question 1.
C₆H₁₂O₆ → C₂H₅OH + CO₂ is ………………. chemical reaction.
A) combination
B) decomposition
C) displacement
D) double decomposition
Answer:
B) decomposition

Question 2.
BaCl₂ + Na₂SO₄ → BaSO₄ + 2 NaCl represents ……………….
i) Decomposition reaction
ii) Displacement reaction
iii) Precipitation reaction
iv) Double displacement reaction
A) Only (i)
B) (ii) & (iii)
C) (iii) & (iv)
D) Only (iv)
Answer:
C) (iii) & (iv)

Question 3.

The above reactions are examples for …………………
A) Chemical combination
B) Chemical decomposition
C) Chemical displacement
D) Double displacement
Answer:
B) Chemical decomposition

Question 4.
The compound which emits Crimson Red colour flame is ………………..
A) Strontium chloride.
B) Cupric chloride.
C) Calcium chloride.
D) Sodium chloride.
Answer:
A) Strontium chloride.

Question 5.
The iron nail dipped in Copper Sulphate solution becomes brown and the blue colour of the Copper Sulphate solution fades. Which type of reaction is this ?
A) Chemical combination
B) Chemical decomposition
C) Double decomposition
D) Displacement
Answer:
D) Displacement

Question 6.
2PbO + C → 2Pb + CO₂ is an example of
A) Oxidation reaction
B) Reduction reaction
C) Redox reaction
D) Corrosion reaction
Answer:
C) Redox reaction

Question 7.
Avogadro’s number among the following is
A) 6.02 × 10²³
B) 6.02 × 10³²
C) 6.02 × 10³³
D) 6.02 × 10²²
Answer:
A) 6.02 × 10²³

Question 8.
Burning of magnesium crackers is a reaction of ………………….
A) reduction
B) cracking
C) oxidation
D) galvanizing
Answer:
C) oxidation

Question 9.
Zn + 2 HCl → ZnCl₂ + H₂ is an example for …………………..
A) Chemical combination
B) Chemical decomposition
C) Chemical displacement
D) Chemical double displacement
Answer:
C) Chemical displacement

Question 10.
The reaction that takes place when quicklime is added to water is ………………..
A) displacement reaction
B) gas liberating reaction
C) heat liberating reaction
D) combustion reaction
Answer:
C) heat liberating reaction

Question 11.
Number of moles of Oxygen needed to produce 4 moles of water on reacting with 4 moles of Hydrogen gas is ………………….
A) 1 mole
B) 2 moles
C) 3 moles
D) 4 moles
Answer:
B) 2 moles

Question 12.
The balanced chemical equation of is …………………….

Answer:

Question 13.
The balanced chemical equation, among the following, is …………………..
A) NaOH + Zn → NaZnO₂ + H₂
B) 2NaOH + Zn → Na₂ZnO₂ + H₂
C) 2NaOH + 2Zn → 2NaZnO₂ + H₂
D) NaOH + 2Zn → NaZn₂O₂ + H₂
Answer:
B) 2NaOH + Zn → Na₂ZnO₂ + H₂

Question 14.
An oxidation reaction involves addition of ……………………
A) oxygen only
B) hydrogen only
C) oxygen or removal of hydrogen
D) hydrogen or removal of oxygen
Answer:
C) oxygen or removal of hydrogen

Question 15.
An arrow pointing downwards in a chemical reaction shows ……………….
A) Evolution of gas
B) Formation of precipitate
C) Oxidation
D) Displacement
Answer:
B) Formation of precipitate

Question 16.
CaO reacts with water to form ………………….
A) CaCO₃
B) Ca(OH)₂
C) CaCl₂
D) Ca(NO₃)₂
Answer:
B) Ca(OH)₂

Question 17.
Ammonia is formed by the reaction of gases …………………
A) H₂ and O₂
B) N₂ and O₂
C) N₂ and H₂
D) H₂ and He
Answer:
C) N₂ and H₂

Question 18.
The reaction Zn + H₂SO₄ → ZnSO₄ + H₂ represents ………………. reaction.
A) combination
B) double displacement
C) displacement
D) decomposition
Answer:
C) displacement

Question 19.
A solution of potassium iodide reacts with lead nitrate to give …………………
A) KNO₃
B) PbI₂
C) A and B
D) PbO
Answer:
C) A and B

Question 20.
The reaction of lead nitrate with dil. HCl represents ……………..
A) combination
B) decomposition
C) displacement
D) double decomposition
Answer:
D) double decomposition

Question 21.
A solution of sodium carbonate reacts with Ca(OH)₂ to give ……………….
A) CaCO₃
B) NaOH
C) Both A and B
D) CaO
Answer:
C) Both A and B

Question 22.
Which reaction is a reversible reaction ?
A) S + O₂ → SO₂
B) PCl₅ ⇌ PCl₃ + Cl₂
C) 2 Na + Cl₂ → 2 NaCl
D) CaC0₃ → CaO + CO₂
Answer:
B) PCl₅ ⇌ PCl₃ + Cl₂

Question 23.
The reaction between Br₂ and KI is a …………………. reaction.
A) combination
B) decomposition
C) displacement
D) double decomposition
Answer:
C) displacement

Question 24.
Due to which of the following enzymes, the surface of the fruit changes the colour on cutting ?
A) amylase
B) tyrosinase
C) lipase
D) peptidase
Answer:
B) tyrosinase

Question 25.
Which of the following vitamins prevents the spoilage of food ?
A) A
B) K
C) C
D) D
Answer:
C) C

Question 26.
NaCl_(aq) + AgNO_3(aq) → AgCl↓_(s) + NaNO_3(aq)
Which type of reaction does the above equation show ?
A) combination reaction
B) decomposition reaction
C) displacement reaction
D) double displacement reaction
Answer:
D) double displacement reaction

Question 27.
To prevent which of the following reactions nitrogen gas is filled in chips flush bags ?
A) oxidation
B) reduction
C) corrosion
D) combustion
Answer:
A) oxidation

Question 28.
Which of the following is formed, when magnesium burns in air ?
A) White coloured magnesium oxide
B) Black coloured magnesium oxide
C) Yellow coloured magnesium oxide
D) Red coloured magnesium oxide
Answer:
A) White coloured magnesium oxide

Question 29.
CuO + H₂ → Cu + H₂O. In this reaction, which one is reduced ?
A) CuO
B) H₂
C) H₂O
D) CU
Answer:
A) CuO

Question 30.
When corrosion of silver occurs black coating appears. The black coating indicates ……………….
A) silver sulphate
B) silver oxide
C) sliver sulphide
D) sliver chloride
Answer:
C) sliver sulphide

Question 31.
CaO + H₂O → Ca(OH)₂ → + Q (heat energy) The above reaction is an example of ……………….
A) combination
B) decomposition
C) displacement
D) double displacement
Answer:
A) combination

Question 32.
Zn + 2HCl → ZnCl₂ + H₂
The above reaction is an example of ………………..
A) combination
B) decomposition
C) displacement
D) double displacement
Answer:
C) displacement

Question 33.
When some metals are exposed to moisture, acids, etc. they tarnish due to formation of respective metal oxide on their surface. This process is called
A) reduction
B) combustion
C) corrosion
D) rancidity
Answer:
C) corrosion

Question 34.
Rising of dough with yeast depends on ……………… of sugars to carbon dioxide and water.
A) rancidity
B) corrosion
C) reduction
D) oxidation
Answer:
D) oxidation

Question 35.
By using which of the following one, we can calculate the number of molecules and atoms of different substances from the equation
A) Molar mass & unified
B) Avagadro’s number
C) Both A and B
D) A Only
Answer:
D) A Only

Question 36.
Which of the following one is hard and does not rust ?
A) iron
B) copper
C) stainless steel
D) none of these
Answer:
C) stainless steel

Question 37.
To slow down which of the following, we keep the food in air tight containers ?
A) corrosion
B) oxidation
C) reduction
D) combustion
Answer:
B) oxidation

Question 38.
Corrosion is a / an …………………… reaction.
A) Oxidation
B) Reduction
C) Redox
D) None of these
Answer:
A) Oxidation

Question 39.
Precipitate in a reaction is indicated by which arrow mark ?
A) →
B) ↑
C) ↓
D) ←
Answer:
C) ↓

Question 40.
Calcium hydroxide is a ………………….. solution.
A) Acidic
B) Basic
C) Neutral
D) Amphoteric
Answer:
B) Basic

Question 41.
A balanced equation contains
A) Equal number of moles of reactants and products
B) Equal number of molecules of reactants and products
C) Equal number of atoms of different elements on reactant side and product side
D) All the above
Answer:
C) Equal number of atoms of different elements on reactant side and product side

Question 42.
Unbalanced equation is called
A) Basic equation
B) Skeleton equation
C) Stoichiometric equation
D) Fundamental equation
Answer:
B) Skeleton equation

Question 43.
A chemical equation which contains the same number of atoms of different elements on reactant side and product side is
A) Skeleton equation
B) Balanced equation
C) Unbalanced equation
D) Any one of the above
Answer:
B) Balanced equation

Question 44.
Metals displace hydrogen gas from dilute acids. This is an example for
A) combination reaction
B) decomposition reaction
C) displacement reaction
D) double decomposition reaction
Answer:
C) displacement reaction

Question 45.
When iron nail dipped in CuSO₄ the nail becomes brown due to
A) deposition of copper on iron
B) dissolution of iron
C) reduction of iron
D) oxidation of Cu
Answer:
A) deposition of copper on iron

Question 46.
Which of the following combinations is wrong ?
A) 2N₂O → 2N₂+ O₂ – decomposition
B) Ca + 2H₂O → Ca(OH)₂ – combination
C) Zn + 2 HCl → ZnCl₂ + H₂ – double decomposition
D) Zn + H₂SO₄ → ZnSO₄ + H₂ – displacement
Answer:
C) Zn + 2 HCl → ZnCl₂ + H₂ – double decomposition

Question 47.
Why does moist Cl₂ act as bleaching agent ?
A) In presence of water, Cl₂ gives nascent hydrogen.
B) In presence of water, Cl₂ gives nascent oxygen.
C) Moist Cl₂ imparts colour to the substance.
D) Moist chlorine liberates nascent chlorine.
Answer:
B) In presence of water, Cl₂ gives nascent oxygen.

Question 48.
The reagent used to remove the colour of the matter is called
A) chlorinating reagent
B) oxidising agent
C) bleaching agent
D) reducing agent
Answer:
C) bleaching agent

Question 49.
Match the following.
Oxide – Colour
A) MgO a) White
B) PbO b) Yellow
C) CuO c) Black
D) CaO d) Colourless
A) 1 – a, 2 – b, 3 – c, 4 – d
B) 1 – a, 2 – b, 3 – d, 4 – c
C) 1 – d, 2 – c, 3 – b, 4 – a
D) 1 – d, 2 – c, 3 – a, 4 – b
Answer:
A) 1 – a, 2 – b, 3 – c, 4 – d

Question 50.

Ca(OH)₂ + CO₂ → Y + H₂O
The X and Y are
A) CaCO₃, Ca(OH)₂
B) Ca(HCO₃)₂, CaCO₃
C) CaCO₃, Ca(HCO₃)₂
D) CaCO₃, CaCO₃
Answer:
D) CaCO₃, CaCO₃

Question 51.
Which of the following statements is wrong ?
A) Conversion of milk into curd is a chemical change.
B) Addition of water to quick lime liberates heat energy.
C) Addition of aqueous Na₂SO₄ to aqueous BaCl₂ forms clear solution.
D) Calcium oxide produces colourless solution when dissolved in water.
Answer:
C) Addition of aqueous Na₂SO₄ to aqueous BaCl₂ forms clear solution.

Question 52.
Match the following :

A) 1 – a, 2 – b, 3 – c, 4 – d
B) 1 – d, 2 – b, 3 – a, 4 – c
C) 1 – b, 2 – d, 3 – c, 4 – a
D) 1 – d, 2 – c, 3 – b, 4 – a
Answer:
B) 1 – d, 2 – b, 3 – a, 4 – c

Question 53.
Rancidity means
A) Improve the quality of food
B) Improve the preservation of food
C) Spoilage of food by oxidation
D) Any one of the above
Answer:
C) Spoilage of food by oxidation

Question 54.
The number of molecules present in 1g of hydrogen
A) 6 × 10²³
B) 3 × 10²³
C) 1 × 10²³
D) 2 × 10²³
Answer:
B) 3 × 10²³

Question 55.
Which of the following is not an exothermic reaction?
A) C + O₂ → CO₂
B) CaO + H₂O → Ca(OH)₂
C) N₂ + O₂ → 2NO
D) CH₄ + 2O₂ → CO₂ + 2H₂O
Answer:
C) N₂ + O₂ → 2NO

Question 56.
Which of the following statements is / are true?
A) Molecular mass is expressed in unified mass (U).
B) 22.4 l of any gas at STP contains 6.023 × 10²³ molecules.
C) 28 g of N₂ at STP occupies 22.4 litres of volume.
D) All are correct.
Answer:
D) All are correct.

Question 57.
Heating of which of the following compounds gives acidic and basic oxide ?
A) Pb(NO₃)₂
B) AgCl
C) CaCO₃
D) All the above
Answer:
C) CaCO₃

Question 58.
Choose double displacement reaction ………………….
A) X + YZ → XZ + Y
B) X + Y → XY
C) XYZ → XY + Z
D) XY + AB → AX + BY
Answer:
D) XY + AB → AX + BY

Question 59.
Which is not true in a balanced equation ?
A) Number of atoms of different elements on both sides are equal.
B) Mass of both sides are equal.
C) Number of charged ions on both sides are equal.
D) Total charges on both sides are equal.
Answer:
C) Number of charged ions on both sides are equal.

Question 60.
Which of the following is an example of displacement reaction ?
A) N₂ + 3H₂ → 2NH₃
B) 2KClO₃ → 2KCl + 3O₂
C) Zn + 2HCl → ZnCl₂ + H₂
D) 2H₂ → O₂ → 2H₂O
Answer:
C) Zn + 2HCl → ZnCl₂ + H₂

Question 61.
Which is true about oxidation ?
A) It involves loss of electrons.
B) It involves addition of oxygen.
C) It involves removal of hydrogen.
D) All are true.
Answer:
D) All are true.

Question 62.
In the equation CuO + H₂ → Cu + H₂O, the substance reduced is ………………
A) H₂
B) CU
C) CuO
D) H₂O
Answer:
C) CuO

Question 63.
Which of the statements about the reaction given below are incorrect ?
2 PbO(s) + C(s) → 2Pb(s) + CO₂(g)
1) Lead is getting reduced. ( )
2) CO₂ is getting oxidised.
3) C is getting oxidised.
4) Pbo is getting reduced.
A) 1 and 2
B) 1 and 3
C) 1, 2, and 3
D) all
Answer:
B) 1 and 3

Question 64.
Silver chloride is mainly used in ……………….
A) In cooking special items
B) In black and white photography
C) A’ and ‘B’
D) In coloured photography
Answer:
B) In black and white photography

Question 65.
Which of the following is not a redox reaction ?
A) AgNO₃ + NaCl → AgCl + NaNO₃
B) CuO + H₂ → Cu + H₂O
C) Mg + Cl₂ → MgCl₂
D) MnO₂ + 4 HCl → MnCl₂ + 2H₂O + 2Cl₂
Answer:
A) AgNO₃ + NaCl → AgCl + NaNO₃

Question 66.
In which of the following, heat energy will be evolved ?
A) Burning of L.P.G.
B) Electrolysis of water
C) Dissolution of ammonium chloride in water
D) Decomposition of silver bromide in the presence of sunlight
Answer:
A) Burning of L.P.G.

Question 67.
When copper vessels are kept over a period of time, these get coated with a green surface. This is due to ………………
1) Oxidation of copper
2) Corrosion of copper
3) Reduction of copper
4) Hydrolysis of copper
A) 1, 2
B) 3, 4
C) 1, 4
D) 2, 4
Answer:
A) 1, 2

Question 68.
The chemical formula of ferric oxide is ………………..
A) Fe₂O
B) Fe₂O₃
C) FeO
D) FeO₂
Answer:
B) Fe₂O₃

Question 69.
Which information is not conveyed by a balanced chemical equation ?
A) Symbols and formulae of all the substances involved in a particular reaction
B) Number of atoms / molecules of the reactants and products involved
C) Physical states of reactants and products
D) Whether a particular reaction is actually possible or not
Answer:
D) Whether a particular reaction is actually possible or not

Question 70.
Which of the following are combination reactions ………………….
1) 2KClO₄ → 2KCl + 4O₂
2) MgO + H₂O → Mg(OH)₂
3) 4Al + 3O₂ → 2Al₂O₃
4) Zn + FeSO₄ → ZnSO₄ + Fe
A) 2, 4
B) 1, 3
C) 3
D) 2, 3
Answer:
D) 2, 3

Question 71.
Which among the following are double displacement reactions ?
1) Pb + CuCl₂ → PbCl₂ + Cu
2) Na₂SO₄ + BaCl₂ → BaSO₄ + 2NaCl
3) C + O₂ = CO₂
4) CH₄ + 2O₂ → CO₂ + 2H₂O
A) 1, 2
B) 2
C) 1, 4
D) 2, 4
Answer:
B) 2

Question 72.
Which of the following is not an exothermic reaction ? …………………
1) C + O₂ → CO₂
2) N₂ + O₂ → 2NO
3) CaCO₃ → CaO + CO₂
4) HCl_(aq) + NaOH_(aq) → NaCl_(aq) + H₂O_(l)
A) 2
B) 2, 3
C) 1
D) 1, 4
Answer:
B) 2, 3

Question 73.

A) brown, grey
B) blue, brown
C) green, brown
D) blue, grey
Answer:
C) green, brown

Question 74.
What is the wrong in the following equation ?
it can be corrected as

Answer:

Question 75.
The following reaction is an example of a …………………
4NH₃(g) + 5O₂(aq) → 4NO(g) + 6H₂O(l)
1) Displacement reaction
2) Combination reaction
3) Redox reaction
4) Neutralisation reaction
A) 2, 3
B) 3, 4
C) 1, 3
D) 1, 4
Answer:
A) 2, 3

Question 76.
In the reaction :
Zn + FeSO₄ → ZnSO₄ + Fe
A) Zn and Fe are both oxidised
B) Fe gets oxidised
C) Zn gets oxidised
D) Zn is an oxidising agent
Answer:
C) Zn gets oxidised

Question 77.
Which of the following are endothermic processes ? …………………….
1) Dilution of sulphuric acid
2) Sublimation of dry ice
3) Condensation of water vapour
4) Evaporation of water
A) 3
B) 1, 3
C) 2
D) 2, 4
Answer:
D) 2, 4

Question 78.
Chemical reactions which occur in presence of sunlight are called ………………. reactions.
A) Thermal
B) Electrolysis
C) Photo chemical
D) Light
Answer:
C) Photo chemical

Question 79.
Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of reaction involved ?
1) displacement reaction
2) precipitation reaction
3) combination reaction
4) double displacement reaction
A) 4
B) 1
C) 2
D) 2, 4
Answer:
D) 2, 4

Question 80.
Which of the following are exothermic processes ?
1) Reaction of water with quick lime
2) Dilution of an acid
3) Evaporation of water
4) Sublimation of camphor (crystals)
A) 1, 2
B) 3, 4
C) 2, 3
D) 1, 4
Answer:
A) 1, 2

Question 81.
Which of the following is not a balanced equation ?
A) Fe + Cl₂ → FeCl₃
B) Zn + S → ZnS
C) Mg + CuSO₄ → MgSO₄ + Cu
D) NaOH + HCl → NaCl + H₂O
Answer:
A) Fe + Cl₂ → FeCl₃

Question 82.
Assertion (A) :
CaO + H₂O → Ca(OH)₂ is a chemical change.
Reason (R) : The original substance does not loss their characteristic properties in chemical change.
A) Both ‘A’ and ‘R’ are correct and ‘R’ supports ‘A’.
B) Both ‘A’ and ‘R’ are correct but ‘R’ does not support ‘A’.
C) ‘A’ is correct but ‘R’ is incorrect.
D) Both ‘A’ and ‘R’ are incorrect.
Answer:
C) ‘A’ is correct but ‘R’ is incorrect.

Question 83.
Assertion (A) : The number of atoms of each element before and after reaction must be the same.
Reason (R) : Law of conservation of mass is followed by every chemical reaction.
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.
B) Both ‘A’ and ‘R’ are correct, but ‘A’ is not supported by ‘R’.
C) ‘A’ is correct, but ‘R’ is incorrect.
D) ‘A’ is incorrect, but ‘R’ is correct.
Answer:
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.

Question 84.
Assertion (A) : All the chemical equations must be balanced.
Reason (R) : Atoms are either created or destroyed in chemical reaction.
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.
B) Both ‘A’ and ‘R’ are correct, but ‘A’ is not supported by ‘R’.
C) ‘A’ is correct, but ‘R’ is incorrect.
D) ‘A’ is incorrect, but ‘R’ is correct.
Answer:
C) ‘A’ is correct, but ‘R’ is incorrect.

Question 85.
Assertion (A) :
2C₃H₈ + 10O₂ → 6CO₂ + 8H₂O is not a balanced equation.
Reason (R) : The coefficients are not the smallest whole numbers.
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.
B) Both ‘A’ and ‘R’ are correct, but ‘A’ is not supported by ‘R’.
C) ‘A’ is correct, but ‘R’ is incorrect.
D) ‘A’ is incorrect, but ‘R’ is correct.
Answer:
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.

Question 86.
Assertion (A) : All the decomposition reactions are endothermic.
Reason (R) : Decomposition reactions require energy in the form of heat, light or electricity.
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.
B) Both ‘A’ and ‘R’ are correct, but ‘A’ is not supported by ‘R’
C) ‘A’ is correct, but ‘R’ is incorrect.
D) ‘A’ is incorrect, but ‘R’ is correct.
Answer:
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.

Question 87.
Assertion (A) : The element zinc has displaced hydrogen from hydrochloric acid.
Reason (R): Generally metals which are less active than hydrogen displaces it from an acid.
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.
B) Both ‘A’ and ‘R’ are correct, but ‘A’ is not supported by ‘R’.
C) ‘A’ is correct, but ‘R’ is incorrect.
D) ‘A’ is incorrect, but ‘R’ is correct.
Answer:
C) ‘A’ is correct, but ‘R’ is incorrect.

Question 88.
Assertion (A) : Fe + CuSO₄ → FeSO₄ + Cu.
Reason (R) : Copper is more reactive than iron.
A) Both ‘A’ and ‘R’ are correct and ‘A’ is supported by ‘R’.
B) Both ‘A’ and ‘R’ are correct, but ‘A’ is not supported by ‘R’.
C) ‘A’ is correct, but ‘R’ is incorrect.
D) ‘A’ is incorrect, but ‘R’ is correct.
Answer:
C) ‘A’ is correct, but ‘R’ is incorrect.

Question 89.
Assertion (A) : Oxidation take place in metals only.
Assertion (B) : Corrosion is an oxidation process.
A) A and B are correct.
B) A is correct, B is incorrect.
C) A is incorrect, B is correct.
D) Both A and B are incorrect.
Answer:
C) A is incorrect, B is correct.

Question 90.
Assertion (A) : Chips packets are filled with Vitamin ‘C’ and Vitamin ‘E’.
Reason (R) : Vitamin ‘C’ and Vitamin ‘E’ prevents oxidation.
A) ‘A’, ‘R’ are correct, A is supported by ‘R’.
B) ‘A’, ‘R’ are correct, A is not supported by ‘R’.
C) ‘A’ is correct, ‘R’ is incorrect.
D) ‘A’ is incorrect, ‘R’ is correct.
Answer:
D) ‘A’ is incorrect, ‘R’ is correct.

Question 91.
Select the correct option given below.
a) Chemical combination is always endothermic.
b) Chemical decomposition is always exothermic.
A) ‘a’ and ‘b’ are correct.
B) ‘a’ is correct and ‘b’ is incorrect.
C) ‘a’ is incorrect and ‘b’ is correct.
D) both ‘a’ and ‘b’ are incorrect.
Answer:
D) both ‘a’ and ‘b’ are incorrect.

Question 92.
Which of the following is true in a completed chemical reaction ?
A) The total mass of the products > total mass of the reactants.
B) The total mass of the products < total mass of the reactants.
C) The total mass of the products = total mass of the reactants.
D) The total mass of the products × total mass of the reactants = 0.
Answer:
C) The total mass of the products = total mass of the reactants.

Question 93.
x KClO₃ → y KCl + z O₂. The respective values of x, y, z are ………………….
A) 1, 2, 3
B) 3, 3, 2
C) 2, 2, 3
D) 2, 2, 2
Answer:
C) 2, 2, 3

Question 94.
A neutralization reaction is a ………………. reaction.
A) decomposition
B) displacement
C) combination
D) double displacement
Answer:
D) double displacement

Question 95.
In which of the following reactions is there only one reactant ?
A) combination
B) decomposition
C) displacement
D) double displacement
Answer:
A) combination

Question 96.
In a decomposition reaction of CuCO₃ which one is formed ?
A) CO₂
B) O₂
C) H₂
D) N₂
Answer:
A) CO₂

Question 97.
The gas liberated when zinc carbonate decomposes is …………………
A) Cl₂
B) CO₂
C) O₂
D) NO₂
Answer:
B) CO₂

Question 98.
Zinc displaces the following gas from sulphuric acid ………………
A) O₂
B) CO₂
C) NO₂
D) H₂
Answer:
D) H₂

Question 99.
Which of the following gases puts off the matchstick when calcium carbonate is heated ?
A) H₂
B) O₂
C) CO₂
D) NO₂
Answer:
C) CO₂

Question 100.
Which of the following gases indicates the brown fumes liberating in the boiling tube, when lead nitrate is heated?
A) H₂
B) O₂
C) CO₂
D) NO₂
Answer:
D) NO₂

Question 101.
Which of the following precipitates is formed, on mixing lead nitrate [Pb(NO₃)₂] with potassium iodide [KI]?
A) Brown coloured PbI₂
B) Green coloured PbI₂
C) Blue coloured PbI₂
D) Yellow coloured PbI₂
Answer:
D) Yellow coloured PbI₂

Question 102.
When corrosion of copper occurs, green coating appears on copper. The green coating indicates
A) Cu
B) Cu₂O
C) CuO
D) CuO₂
Answer:
C) CuO

Question 103.
A substance is in light yellow colour. If we put it in sunlight, it changes into grey colour. What is the substance ?
A) Lead iodide
B) Potassium iodide
C) Silver bromide
D) HCl
Answer:
C) Silver bromide

Question 104.
x H₂ + y O₂ > z H₂O. The values of
x, y, z are
A) x = 1, y = 1, z = 1
B) x = 2, y = 1, z = 2
C) x = 2, y = 2, z = 2
D) x = 2, y = 1, z = 1
Answer:
B) x = 2, y = 1, z = 2

Question 105.
Which of the following is not a double decomposition reaction ?
A) Pb(NO₃)₂ + 2 KI → PbI₂ + 2KNO₃
B) NaCl + AgNO₃ → AgCl + NaNO₃
C) Na₂SO₄ + BaCl₂ → BaSO₄ + 2NaCl
D) Fe + CuSO₄ → FeSO₄ + Cu
Answer:
D) Fe + CuSO₄ → FeSO₄ + Cu

Question 106.
Why are food materials packed in air tight containers ?
A) To preserve the nutrients
B) To prevent the spoilage by oxidation
C) To prevent the spoilage by reduction
D) To improve the taste
Answer:
B) To prevent the spoilage by oxidation

Question 107.
Heating of Pb(NO₃)₂ gives two gases ‘X’ and ‘Y’ The colour of X and Y is
A) X = Colourless, Y = Colourless
B) X = Red, Y = Brown
C) X = Brown, Y = Colourless
D) X = Green, Y = Yellow
Answer:
C) X = Brown, Y = Colourless

Question 108.
In electrolysis of water experiment, the ratio of volumes of oxygen and hydrogen gases evolved is ………………….
A) 1 : 2
B) 2 : 1
C) 1 : 1
D) 3 : 1
Answer:
A) 1 : 2

Question 109.
The process of preparing slaked lime by adding water to quicklime is this type of chemical reaction.
A) Decomposition reaction
B) Exothermic reaction
C) Endothermic reaction
D) Displacement reaction
Answer:
B) Exothermic reaction

Question 110.
If the gas liberated in an experiment allows the burning splinter to continue burning more brightly in its presence, the gas is ………………….
A) oxygen
B) nitrogen
C) hydrogen
D) carbon dioxide
Answer:
A) oxygen

Question 111.
Solutions of Copper sulphate, Iron sulphate and Sodium sulphate are marked as X, Y and Z respectively. Few pieces of Aluminium are added to each solution.
In which solutions, change will be observed ?
A) X and Y
B) Y and Z
C) X and Z
D) X, Y and Z
Answer:
A) X and Y

Question 112.
When a small piece of zinc metal is added to a solution of copper sulphate and on heating the products formed are ………………
A) CuO
B) ZnSO₄ + Cu
C) ZnO
D) H₂↑
Answer:
B) ZnSO₄ + Cu

Question 113.
Which of the following precipitates is formed on mixing sodium sulphate with barium chloride solution?
A) White precipitate of barium sulphate
B) Black precipitate of barium sulphate
C) Yellow precipitate of barium sulphate
D) Red precipitate of barium sulphate
Answer:
A) White precipitate of barium sulphate

Question 114.
Which of the following is the colour of hydrous copper sulphate (CuSO₄) ?
A) Red
B) White
C) Yellow
D) Blue
Answer:
D) Blue

Question 115.
When dilute hydrochloric acid is added to iron filings
A) hydrogen gas and iron chloride are formed
B) chlorine gas and iron hydroxide are formed
C) no reaction takes place
D) iron salt and water are produced
Answer:
A) hydrogen gas and iron chloride are formed

Question 116.
Which of the following metals fails to evolve hydrogen gas with dilute HCl? ………………….
A) Iron
B) Aluminium
C) Zinc
D) Copper
Answer:
D) Copper

Question 117.
In the electrolysis of water, anode
A) has positive charge
B) is connected to negative terminal of battery
C) is neutral
D) has negative charge
Answer:
A) has positive charge

Question 118.
A student takes about 2 ml ethanoic acid in a dry test tube and adds a pinch of sodium hydrogen carbonate to it. He reports the following observations
1) Immediately a colourless and odourless gas evolves with a brisk effervescence
2) The gas turns lime water to milky when passed through it.
3) The gas burns with an explosion when a burning splinter is brought near to it.
4) The gas extinguishes the burning splinter that is brought near to it
A) 1, 2, 3
B) 2, 3, 4
C) 3, 4, 1
D) 1, 2, 4
Answer:
D) 1, 2, 4

Question 119.
Copper is more reactive than silver. This is explained as
Cu + AgNO₃(aq) → CuO(NO₃)₂(aq) + 2Ag. It reveals
A) It displaces silver from silver nitrate thus giving shining appearance on top
B) It decomposes silver from silver nitrate giving no appearance change
C) Both A’ and ‘B’ sometimes
D) Not explained
Answer:
A) It displaces silver from silver nitrate thus giving shining appearance on top

Question 120.
The correct observation made by the student after putting clean pieces of iron in the test tube containing zinc sulphate is as shown in figure :

A) Solution becomes colourless and zinc gets deposited on iron
B) Solution becomes green and zinc gets deposited on iron
C) Iron pieces get dissolved in the solution making it green
D) No reaction is observed
Answer:
D) No reaction is observed

Question 121.
A student added dilute HCl to a test tube containing Zn granules and made following observations ?
1) The Zn surface became dull and black
2) A gas evolved which burnt with a pop sound
3) The solution remained colourless
A) 1, 2
B) 2, 3
C) 2, 3
D) all?
Answer:
B) 2, 3

Question 122.
Assertion (A) : Heat is released on reaction of water with CaO,
Reason (R) : It is an exothermic reaction.
A) Both (A), (R) are correct, Assertion supports Reason.
B) Both (A), (R) are correct, Assertion does not support Reason.
C) (A) is correct, (R) is wrong.
D) (A) is wrong, (R) is correct.
Answer:
A) Both (A), (R) are correct, Assertion supports Reason.

Question 123.

‘X’ indicates
A) Salt
B) Metal
C) Non-metal
D) Base
Answer:
B) Metal

Question 124.

Identify the wrong in the figure.
A) Chemicals used
B) Place of burner
C) Direction of gas
D) Position of the corks
Answer:
C) Direction of gas

Question 125.

Pb(NO₃)₂ KI
What does ‘X’ indicate ?
A) PbK
B) PbI₂
C) PbKI(NO₃)₂
D) NO₃Pb
Answer:
B) PbI₂

Question 126.
Label ‘X’ and ‘Y’
A) O₂, H₂
B) Cl₂, O₂
C) H₂, O₂
D) O₂, Cl₂
Answer:
A) O₂, H₂

Question 127.
A balanced chemical equation is appreciable because, it gives
A) mass – mass relationship
B) mass – volume relationship
C) volume – volume relationship
D) above all
Answer:
D) above all

Question 128.
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂. This reaction is appreciable, because it gives us
A) sunlight
B) chlorophyll
C) glucose
D) heat
Answer:
C) glucose

Question 129.
Vitamin ‘C’ and Vitamin ‘E’ are appreciable because, they can prevent
A) Rancidity
B) Alloying
C) Reduction
D) Above all
Answer:
A) Rancidity

Question 130.
We should appreciate alloys, because they
A) do not corrode
B) have hardness
C) have strength
D) above all
Answer:
D) above all

Question 131.
Which of the following is an oxidation process observed in daily life ?
A) Black coating on silver
B) Formation of green compound on copper
C) Fermentation
D) All the above
Answer:
D) All the above

Question 132.
Chemically rust is
A) only ferric oxide
B) hydrated ferric oxide
C) hydrated cuprous oxide
D) hydrated ferrous oxide
Answer:
B) hydrated ferric oxide

Question 133.
Identify methods for prevention of rusting from the following.
1) By applying oils and greases on surfaces
2) By paint coating on surfaces
3) By galvanisation
4) By keeping the iron articles in air
A) 1, 2
B) 1, 2, 3
C) 4
D) 2, 4
Answer:
B) 1, 2, 3

Question 134.
Rancidity is ……………….. reaction.
A) Reduction
B) Oxidation
C) Redox
D) Double displacement
Answer:
B) Oxidation

Question 135.
Stainless steel is an alloy of iron with elements like ………………
A) Cu, Ni, Cr
B) C, Ni, Cr
C) Fe, C, Cr
D) Fe, Ni, Cr
Answer:
B) C, Ni, Cr

Question 136.
Which of the following gases can be used for storage of fresh sample of an oil for a long time ?
1) Carbon dioxide
2) Helium
3) Nitrogen
4) Oxygen
A) 1 or 4
B) 3 or 4
C) 2 or 3
D) 1 or 2
Answer:
C) 2 or 3

Question 137.
Coating of thin layer of zinc on metal surface is called …………………..
A) Galvanizing
B) Zinc coating
C) Corrosion
D) Rusting
Answer:
A) Galvanizing

Question 138.
Three beakers labelled as A, B and C each containing 25 ml of water were taken. A small amount of NaOH, an hydrous CuSO₄, and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in temperature of solution, contained in beakers A and B, where as in beaker C, the temperature of the
solutions falls. Which one of the following statements is / are correct ?
1) In beakers ‘A’ and ‘B’, exothermic process has occurred
2) In beakers ‘A’ and ‘B’, endothermic process has occurred
3) In beaker ‘C’, exothermic process has occurred
4) In beaker ‘C’, endothermic process has occurred
A) 2
B) 2, 3
C) 1, 4
D) 1
Answer:
C) 1, 4

Question 139.
Quick lime reacts vigorously with water releasing a large amount of heat. Which type of reaction is this ?
1) Precipitation reaction
2) Combination reaction
3) Decomposition reaction
4) Exothermic reaction
A) 1, 2
B) 2, 3
C) 2, 4
D) 4
Answer:
C) 2, 4

Question 140.
What is the difference among the following chemical combination reactions ?
1) 2H₂ + O₂ → 2H₂O
2) 2CO + O₂ → 2CO₂
3) NH₃ + HCl → NH₄Cl
A) In reactants of first equation both are elements.
B) In reactants of second equation one is compound and other one is element.
C) In equation three both the reactants are compounds.
D) All are correct.
Answer:
D) All are correct.

Practice the AP 9th Class Physical Science Bits with Answers Chapter 10 Work and Energy on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 9th Class Physical Science Bits 10th Lesson Work and Energy with Answers

Question 1.
The conditions need to be satisfied in order to say that work has been done are
A) a force should act on the object
B) the object must be displaced
C) both A and B
D) no condition is required
Answer:
C) both A and B

Question 2.
Work is ………………. quantity.
A) vector
B) scalar
C) unit less
D) can’t say
Answer:
B) scalar

Question 3.
The formula W = Fs is used in only ………………. motion of the object.
A) circular
B) oscillatory
C) translatory
D) trajectory
Answer:
C) translatory

Question 4.
If positive work is done on a system, its energy
A) decreases
B) increases
C) becomes zero
D) remains same
Answer:
B) increases

Question 5.
The kinetic energy of an object depends on
A) mass
B) speed
C) gravitational force
D) none
Answer:
C) gravitational force

Question 6.
The potential energy of an object increases with its
A) height or position
B) mass
C) velocity
D) none
Answer:
A) height or position

Question 7.
The sum of kinetic energy and the potential energy of an object is called its
A) total energy
B) mechanical energy
C) system of energy
D) energy conservation
Answer:
B) mechanical energy

Question 8.
Rate of doing work or rate of transfer of energy is
A) work
B) energy
C) power
D) time
Answer:
C) power

Question 9.
The measure of speed of the work done is
A) power
B) energy
C) work
D) time
Answer:
A) power

Question 10.
The capacity to do a work is called
A) energy
B) power
C) work
D) strength
Answer:
A) energy

Question 11.
Work is equal to the product of ……………….. and …………………
A) force, time
B) force, displacement
C) force, velocity
D) force, acceleration
Answer:
B) force, displacement

Question 12.
Among these which is a scalar quantity ………………..
A) velocity
B) acceleration
C) momentum
D) work
Answer:
D) work

Question 13.
S.I. Unit of work is ………………….
A) Erg
B) Joule
D) Pascal
C) Newton
Answer:
B) Joule

Question 14.
1 N – m is equal to ……………….
A) Erg
B) Newton
C) Pascal
D) Joule
Answer:
D) Joule

Question 15.
In case of a vertically up thrown body, the speed of the body while moving up ……………….
A) increases
B) decreases
C) no change
D) both A & B
Answer:
B) decreases

Question 16.
If work has positive value, the body on which the work has been done would energy.
A) gain
B) lose
C) no change in
D) none of these
Answer:
A) gain

Question 17.
If work has negative value, the body on which the work has been done would ………………. energy.
A) gain
B) lose
C) without change
D) none of these
Answer:
B) lose

Question 18.
The capacity of doing work by an object depends on ………………. and of the object which is doing work.
A) position, state
B) length, breadth
C) area, volume
D) pressure, density
Answer:
A) position, state

Question 19.
When work is done, energy will be ……………… from one object to other.
A) transferred
B) lost
C) gained
D) none of these
Answer:
A) transferred

Question 20.
The biggest natural and primary source of energy for us is the ………………….
A) Moon
B) Jupiter
C) Sun
D) Mars
Answer:
C) Sun

Question 21.
The energy possessed by an object due to its motion is called ……………… energy.
A) potential
B) kinetic
C) mechanical
D) electrical
Answer:
B) kinetic

Question 22.
The numerical expression for kinetic energy is K.E. = ………………….
A) \(\frac{1}{2}\) mv
B) \(\frac{1}{2}\) mv²
C) \(\frac{\mathrm{mv}^{2}}{\mathrm{r}}\)
D) \(\frac{1}{2}\)m²v
Answer:
B) \(\frac{1}{2}\) mv²

Question 23.
P.E. = …………………
A) \(\frac{1}{2}\) mv²
B)\(\frac{1}{2}\) mv
C) mgh
D) \(\frac{\mathrm{mg}}{\mathrm{h}}\)
Answer:
C) mgh

Question 24.
In an iron box ……………….. energy converts into ………………… energy.
A) electrical, sound
B) electrical, magnetic
C) electrical, heat
D) electrical, light
Answer:
C) electrical, heat

Question 25.
Power = ……………….
A) \(\frac{\text { Work }}{\text { Time }}\)
B) \(\frac{\text { Time }}{\text { Work }}\)
C) Work × Time
D) None of these
Answer:
A) \(\frac{\text { Work }}{\text { Time }}\)

Question 26.
The unit of power is ……………….
A) Erg
B) Joule/sec.
C) Watt
D) Both B & C
Answer:
D) Both B & C

Question 27.
Kinetic energy of an object increases with its ………………..
A) acceleration
B) speed
C) volume
D) density
Answer:
B) speed

Question 28.
If the displacement of the object is in the direction opposite to the direction of force applied, then the work done is ………………….
A) positive
B) negative
C) 0
D) none of these
Answer:
B) negative

Question 29.
Work (W) = ………………..
A) F / s
B) F × s
C) s / F
D) none of these
Answer:
B) F × s

Question 30.
The capacity to do work is called …………………
A) power
B) work
C) energy
D) force
Answer:
C) energy

Question 31.
Mechanical energy = ……………….
A) PE + KE
B) PE / KE
C) KE / PE
D) PE – KE
Answer:
A) PE + KE

Question 32.
1 Watt = ………………..
A) 1 erg/s
B) 1 J/s
C) 1 Newton/ sec
D) 1 Newton . sec
Answer:
B) 1 J/s

Question 33.
Work done by gravitational force on a freely falling body ………………..
A) negative
B) 0
C) positive
D) both A & C
Answer:
C) positive

Question 34.
Work done by friction on a body moving on plain ground ………………….
A) positive
B) negative
C) 0
D) none of these
Answer:
B) negative

Question 35.
Work done by a porter standing with luggage on his head is …………………….
A) positive
B) negative
C) 0
D) none of these
Answer:
C) 0

Question 36.
When a ball is moving on plain ground, the work done by the frictional force on the ball is
A) positive
B) negative
C) zero
D) undefined
Answer:
B) negative

Question 37.
A boy pushes wall. The work done by the boy is
A) positive
B) negative
C) zero
D) undefined
Answer:
C) zero

Question 38.
Human beings or machines need ………………to do work.
A) energy
B) food
C) petrol
D) fuel
Answer:
A) energy

Question 39.
Work is said to be done in the following case
A) Rangaiah is pushing a huge rock but he fail to move it
B) Seetha is pulling a toy car
C) Priyanka is working hard for her examinations
D) A porter is waiting on the platform of a railway station with luggage on his head.
Answer:
B) Seetha is pulling a toy car

Question 40.
The energy possessed by a wounded spring in a toy car is
A) kinetic energy
B) spring energy
C) muscular energy
D) potential energy
Answer:
D) potential energy

Question 41.
The energy possessed by a running athlete is
A) potential energy
B) kinetic energy
C) muscular energy
D) food energy
Answer:
B) kinetic energy

Question 42.
Energy possessed by the blowing wind is ………………….. energy.
A) potential
B) mechanical
C) kinetic
D) magnetic
Answer:
C) kinetic

Question 43.
The energy possessed by a body due to its height or position is ………………… energy.
A) potential
B) kinetic
C) mechanical
D) muscular
Answer:
A) potential

Question 44.
The sum of the kinetic energy and the potential energy of an object is called its ……………………. energy.
A) muscular
B) electric
C) magnetic
D) mechanical
Answer:
D) mechanical

Question 45.
The total mechanical energy of an aeroplane at rest is ………………….
A) mgh
B) \(\frac{1}{2}\) mv²
C) zero
D) cannot say
Answer:
C) zero

Question 46.
In fuels like petroleum, coal, etc ……………… energy is stored in them.
A) physical
B) electrical
C) magnetical
D) chemical
Answer:
D) chemical

Question 47.
Ratio of doing work or rate of transfer of energy is defined as ……………….
A) work
B) power
C) capacity
D) impulse
Answer:
B) power

Question 48.
In case of a freely falling body ……………… energy is gradually converted into …………………. energy at a certain height ‘h’.
A) potential, kinetic
B) kinetic, potential
C) kinetic, kinetic
D) potential, potential
Answer:
A) potential, kinetic

Question 49.
The water stored in overhead tanks, possesses ………………. energy.
A) mechanical
B) kinetic
C) potential
D) chemical
Answer:
C) potential

Question 50
…………….. energy is used by plants for preparing their food.
A) Potential
B) Kinetic
C) Mechanical
D) Solar
Answer:
D) Solar

Question 51.
Work done by force applied by hands of a man swimming in a pond is ………………
A) negative
B) positive
C) 0
D) none of these
Answer:
A) negative

Question 52.
Energy of running water is ……………….. energy.
A) potential
B) kinetic
C) mechanical
D) none of these
Answer:
B) kinetic

Question 53.
Energy of a raised hammer is ……………… energy.
A) potential
B) kinetic
C) mechanical
D) magnetic
Answer:
A) potential

Question 54.
‘Work’has
A) Only direction, no magnitude
B) Only magnitude, no direction
C) Both magnitude and direction
D) No magnitude, no direction
Answer:
B) Only magnitude, no direction

Question 55.
Power is defined as
P) rate of doing work
Q) rate of transfer of energy
R) sum of kinetic and potential energy
A) P only
B) Q and R
C) P and Q
D) P, Q and R
Answer:
C) P and Q

Question 56.
When speed of the ball is doubled its kinetic energy is
A) Remains same
B) Gets doubled
C) Becomes half
D) Becomes 4 times
Answer:
D) Becomes 4 times

Question 57.
Chaitanya performs 300J of work in 5 minutes. The power delivered by her is
A) 60 W
B) \(\frac{1}{60}\) W
C) 1 W
D) 0 W
Answer:
C) 1 W

Practice the AP 9th Class Physical Science Bits with Answers Chapter 11 Sound on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 9th Class Physical Science Bits 11th Lesson Sound with Answers

Question 1.
Sound travels in the air in the form of
A) pulses
B) corpuscules
C) waves
D) particles
Answer:
C) waves

Question 2.
Longitudinal waves involves change in …………………. of the medicine.
A) density
B) shape
C) velocity
D) temperature
Answer:
A) density

Question 3.
Transverse waves involves change in ………………. of the medium.
A) density
B) shape
C) velocity
D) temperature
Answer:
B) shape

Question 4.
Longitudinal wave of the following is
A) light wave
B) water wave
C) sound wave
D) none
Answer:
C) sound wave

Question 5.
The maximum disturbance of particles in the medium on either side of mean position is called
A) wavelength
B) frequency
C) wave speed
D) amplitude
Answer:
D) amplitude

Question 6.
The time taken for one oscillation is called
A) frequency
B) time period
C) wavelength
D) wave speed
Answer:
B) time period

Question 7.
The matter or the substance through which sound is transmitted is called the …………………
A) object
B) medium
C) substance
D) quantity
Answer:
B) medium

Question 8.
The distance between two consecutive compressions is ……………….
A) speed
B) wavelength
C) frequency
D) time period
Answer:
B) wavelength

Question 9.
When a sound wave travels in air …………….. and ……………… of air at a place varies.
A) volume, density
B) pressure, volume
C) density, pressure
D) frequency, speed
Answer:
C) density, pressure

Question 10.
The regions where the density and pressure of particles is high are called as …………………
A) crusts
B) troughs
C) compressions
D) rarefactions
Answer:
C) compressions

Question 11.
The regions where the density and pressure of particles is low are called as ………………….
A) crusts
B) troughs
C) compressions
D) rarefactions
Answer:
D) rarefactions

Question 12.
Sound waves are ……………….. waves.
A) stationary
B) longitudinal
C) transverse
D) electromagnetic
Answer:
B) longitudinal

Question 13.
If the particles of the medium vibrate along the direction of wave, then the wave is called a …………………..
A) longitudinal
B) transverse
C) stationary
D) electromagnetic
Answer:
A) longitudinal

Question 14.
The unit of wavelength in S.l. system is …………………..
A) metre
B) hertz
C) decibel
D) m/s
Answer:
A) metre

Question 15.
The unit of frequency of wave is ………………….
A) metre
B) hertz
C) decibel
D) second
Answer:
B) hertz

Question 16.
Relation between time period (T) and frequency (υ) is …………………..
A) T = \(\frac{1}{υ}\)
B) υ = \(\frac{1}{\mathrm{~T}}\)
C) υ = T
D) Both A & B
Answer:
D) Both A & B

Question 17.
Relation between speed of sound, frequency and wavelength is ………………
A) v = λυ
B) υ = vλ
C) λ = vυ
D) λvυ = 1
Answer:
A) v = λυ

Question 18.
Speed of sound in water at 20°C = …………………
A) 330 m/s
B) 5500 m/s
C) 1484 m/s
D) 220 m/s
Answer:
C) 1484 m/s

Question 19.
Speed of sound in air at 20°C is ……………….
A) 343.2 m/s
B) 1236 km/hr
C) 330 m/s
D) Both A & B
Answer:
D) Both A & B

Question 20.
Pitch of sound depends on …………….
A) frequency
B) amplitude
C) wavelength
D) none of these
Answer:
A) frequency

Question 21.
Loudness of sound depends on …………………..
A) frequency
B) amplitude
C) wavelength
D) none of these
Answer:
B) amplitude

Question 22.
Reflection of sound will be better on ………………. surface than …………….. surface.
A) smooth, rough
B) rough, smooth
C) inclined, inverted
D) straight, inclined
Answer:
B) rough, smooth

Question 23.
SONAR stands for …………………..
A) Sonographic Navigation And Ranging
B) Sonographic Notation And Rating
C) Sound Notation And Rating
D) Sound Navigation And Rating
Answer:
A) Sonographic Navigation And Ranging

Question 24.
Region of low dense particles ………………….
A) compression
B) rarefaction
C) crust
D) trough
Answer:
B) rarefaction

Question 25.
Region of high dense particles is ………………
A) compression
B) rarefaction
C) crust
D) trough
Answer:
A) compression

Question 26.
Number of oscillations in one second is called ……………………
A) wavelength
B) frequency
C) time period
D) amplitude
Answer:
B) frequency

Question 27.
Maximum variation in the density is ………………
A) wavelength
B) frequency
C) time period
D) amplitude
Answer:
D) amplitude

Question 28.
Distance between two consecutive compressions is …………………..
A) wavelength
B) frequency
C) time period
D) amplitude
Answer:
A) wavelength

Question 29.
Sound is produced by
A) any body
B) vibrating body
C) a body in motion
D) bodies having different shapes
Answer:
B) vibrating body

Question 30.
The characteristic of sound which distinguishes between a shrill sound and a growling sound is
A) pitch
B) loudness
C) quality
D) amplitude
Answer:
A) pitch

Question 31.
Loudness of sound is measured in
A) Hertz
B) Meters
C) Decibels
D) Seconds
Answer:
C) Decibels

Question 32.
The audible range of frequency for an average person is
A) 20 Hz – 200 Hz
B) 20 Hz – 20 kHz
C) 2 kHz – 20 kHz
D) 2000 Hz – 200 kHz
Answer:
B) 20 Hz – 20 kHz

Question 33.
The loudness of sound is considered normal if it is between ………………
A) 50 dB to 60 dB
B) 80 dB
C) 20 dB
D) more than 120 dB
Answer:
A) 50 dB to 60 dB

Question 34.
The decibel level of jet engine taking off is ……………..
A) 80 dB
B) 100 dB
C) 120 dB
D) 60 dB
Answer:
C) 120 dB

Question 35.
Statement – I : If frequency of sound is less than 20 Hz, then they are called infrasonic sounds.
Statement – II : If frequency of sound is more than 20 Hz, then they are called infrasonic sounds.
A) Both the statements I & II are true.
B) Statement -1 is true and statement -II is false.
C) Statement -1 is false and statement – II is true.
D) Both the statements I & II are false.
Answer:
A) Both the statements I & II are true.

Question 36.
Quality of a musical note depends on ……………….
A) instrument
B) wavelength
C) frequency
D) wave form
Answer:
D) wave form

Question 37.
Sound of frequency less than 20 Hz is known as …………….. sound.
A) infrasonic
B) ultrasonic
C) echo
D) reverberation
Answer:
A) infrasonic

Question 38.
Sound of frequency greater than 20 kHz is known as ………………..
A) infrasonic
B) ultrasonic
C) echo
D) audible range
Answer:
B) ultrasonic

Question 39.
The sounds heard by bat is upto …………….
A) 50 KHz
B) 25 KHz
C) 100 KHz
D) 5 KHz
Answer:
C) 100 KHz

Question 40.
The maximum limit sounds heard by dog is ………………….
A) 50 KHz
B) 25 KHz
C) 100 KHz
D) 5 KHz
Answer:
A) 50 KHz

Question 41.
The unit for intensity of sound is ……………….
A) hertz
B) metre
C) m/s
D) decibel
Answer:
D) decibel

Question 42.
Adjacent picture is one of application of

A) Sound
B) Ultrasound
C) SONAR
D) All
Answer:
B) Ultrasound

Question 43.
Adjacent picture represent the phenomenon of

A) Sound
B) Ultrasound
C) SONAR
D) All
Answer:
C) SONAR

Question 44.
Echo is a reflected sound, reaches our ear, after direct sound in
A) lessthan 0.1s
B) more than 0.1s
C) exactly at 0.1s
D) any time
Answer:
B) more than 0.1s

Question 45.
Using ultrasounds in the imaging of organs like liver, uterus, etc. is called as
A) radiography
B) echography
C) ultrasonography
D) magnetic resonance imaging
Answer:
C) ultrasonography

Question 46.
The location of under water objects can be determined by using
A) SONAR
B) Ultrasound
C) X-ray
D) Light waves
Answer:
A) SONAR

Question 47.
A tabla and a guitar are played at a time. We can identify the sound from which instrument it is coming by the character of
A) pitch
B) loudness
C) quality
D) wave speed
Answer:
C) quality

Question 48.
If the particles of the medium vibrate perpendicular to the direction of wave, then the wave is called a …………………
A) longitudinal
B) transverse
C) stationary
D) electromagnetic
Answer:
B) transverse

Question 49.
As age increases, the audible range of frequency of sound …………………
A) increases
B) decreases
C) both A & B
D) none of these
Answer:
B) decreases

Question 50.
While using SONAR, ……………….. can be utilised to determine the shape and size of the object.
A) refraction from various positions
B) reflection from various angles
C) both A & B
D) none of these
Answer:
B) reflection from various angles

Question 51.
Which of the following is not a characteristic of musical sound ?
A) Wavelength
B) Pitch
C) Loudness
D) Quality
Answer:
C) Loudness

Question 52.
Sound travels in a medium means
A) The medium travels
B) The particles of the medium travels
C) The sound travels
D) The disturbance travels
Answer:
D) The disturbance travels

Question 53.

Which Note has more pitch?
A) Sa
B) re
C) ga
D) ma
Answer:
D) ma

Question 54
Identify the wrong pair among the following.
A) (Pitch, Frequency)
B) (Echo, Refraction)
C) (Quality, Waveform)
D) (Loudness, Amplitude)
Answer:
B) (Echo, Refraction)

Question 55.
Assume that the atmosphere is absent on earth, then the velocity of the sound wave in this situation is
A) 3 × 10⁸ ms^-1
B) 331.2 ms^-1
C) 3 × 10^-8 ms^-1
D) doesn’t propagate
Answer:
D) doesn’t propagate

Practice the AP 9th Class Physical Science Bits with Answers Chapter 8 Gravitation on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 9th Class Physical Science Bits 8th Lesson Gravitation with Answers

Question 1.
In a uniform circular motion ………………… is constant.
A) speed
B) force
C) gravitation
D) weight
Answer:
A) speed

Question 2.
Which of the following quantity always changes in a uniform circular motion ?
A) direction of gravitation
B) direction of velocity
C) mass of the object
D) none
Answer:
B) direction of velocity

Question 3.
When a body is in uniform circular motion …………… force acts on it.
A) gravitational force
B) centrifugal force
C) centripetal force
D) normal force
Answer:
C) centripetal force

Question 4.
Centripetal force acts
A) towards the centre of the circle
B) away from the centre of the circle
C) in a tangential direction
D) along the circular path
Answer:
A) towards the centre of the circle

Question 5.
Acceleration due to gravity is independent of
A) speed of the object
B) gravitational force on the object
C) mass of the object
D) mass of the earth
Answer:
C) mass of the object

Question 6.
Which of the following quantities remain constant in the planetory motion as seen from the sun
A) speed
B) angular speed
C) kinetic energy
D) angular momentum
Answer:
D) angular momentum

Question 7.
A stone is released from an elevator going up with an acceleration a, the acceleration of the stone after release
A) a upwards
B) (g – A) upwards
C) (g – A) downwards
D) g downwards
Answer:
D) g downwards

Question 8.
Relation between ‘g’ and ‘G’ is
A) g = G
B) g = GM/R²
C) G = gM/R²
D) GR² = gM
Answer:
B) g = GM/R²

Question 9.
The point where total weight appears to act is called
A) centre of gravity
B) centre of equilibrium
C) mid point
D) equilibrium point
Answer:
A) centre of gravity

Question 10.
If the line through the centre of gravity falls inside the base of the object, then the object will be
A) weightless
B) unstable
C) stable
D) freely falling
Answer:
C) stable

Question 11.
If the line through the centre of gravity falls out side the base of the object, then the object will be
A) weightless
B) unstable
C) stable
D) freely falling
Answer:
B) unstable

Question 12.
The motion of a body with constant speed in circular path is known as ……………
A) circular motion
B) rotatory motion
C) uniform circular motion
D) none of these
Answer:
C) uniform circular motion

Question 13.
In uniform circular motion …………………….. is constant.
A) speed
B) velocity
C) acceleration
D) momentum
Answer:
A) speed

Question 14.
The acceleration which can change only the direction of velocity of a body is called ………………..
A) retardation
B) deceleration
C) negative acceleration
D) centripetal acceleration
Answer:
D) centripetal acceleration

Question 15.
The net force which can change only the direction of the velocity of a body is called ……………………
A) gravitational force
B) frictional force
C) centripetal force
D) electrical force
Answer:
C) centripetal force

Question 16.
The direction of centripetal force is ……………….. the centre of the circle.
A) towards
B) away
C) left side of
D) right side of
Answer:
A) towards

Question 17.
Motion of moon around the earth is …………………. motion.
A) vibrational
B) circular
C) rotational
D) uniform circular
Answer:
D) uniform circular

Question 18.
The moon takes ………………….. for a complete revolution around the earth.
A) 25 days
B) 27.3 days
C) 30 days
D) 35 days
Answer:
B) 27.3 days

Question 19.
Acceleration due to gravity is independent of …………………….. of the object.
A) mass
B) volume
C) weight
D) density
Answer:
A) mass

Question 20.
The average position of weight distribution is simply the ……………………
A) centre of velocity
B) centre of momentum
C) centre of gravity
D) centre of acceleration
Answer:
C) centre of gravity

Question 21.
The location of ……………………… is important for stability.
A) centre of velocity
B) centre of curvature
C) centre of momentum
D) centre of gravity
Answer:
D) centre of gravity

Question 22.
Gravitational force can be called …………………….
A) contact force
B) non-contacting force
C) force at a distance
D) both B & C
Answer:
D) both B & C

Question 23.
Two particles of same mass ‘m’ go round a circle of radius ‘r’ under the action of their mutual gravitational attraction. The speed of each particle is ……………………
A) \(\sqrt{\frac{\mathrm{GM}}{\mathrm{r}^{2}}}\)
B) \(\sqrt{\frac{\mathrm{GMm}}{\mathrm{r}}}\)
C) \(\sqrt{\frac{\mathrm{GM}}{4 \mathrm{r}}}\)
D) \(\sqrt{\frac{\mathrm{GM}^{2}}{\mathrm{r}}}\)
Answer:
C) \(\sqrt{\frac{\mathrm{GM}}{4 \mathrm{r}}}\)

Question 24.
Centripetal acceleration ……………..
A) \(\frac{\mathrm{v}}{\mathrm{r}}\)
B) \(\frac{\mathrm{v}^{2}}{\mathrm{r}}\)
C) \(\frac{\mathrm{v}^{2}}{\mathrm{r}^{2}}\)
D) \(\frac{\mathrm{v}}{\mathrm{r}^{3}}\)
Answer:
B) \(\frac{\mathrm{v}^{2}}{\mathrm{r}}\)

Question 25.
Centripetal force ………………
A) \(\frac{\mathrm{mv}}{\mathrm{R}}\)
B) \(\frac{\mathrm{mv}^{2}}{\mathrm{R}^{3}}\)
C) \(\frac{\mathrm{mv}^{2}}{\mathrm{R}}\)
D) \(\frac{\mathrm{m}^{2} \mathrm{v}}{\mathrm{R}}\)
Answer:
C) \(\frac{\mathrm{mv}^{2}}{\mathrm{R}}\)

Question 26.
Time period of a body moving around a body of radius R, with velocity v is …………………
A) T = \(\frac{2 \pi \mathrm{R}}{\mathrm{v}}\)
B) T = \(\frac{\mathrm{v}}{2 \pi \mathrm{R}}\)
C) T = \(\frac{2 \pi \mathrm{v}}{\mathrm{R}}\)
D) T= \(\frac{1}{2 \pi R v}\)
Answer:
A) T = \(\frac{2 \pi \mathrm{R}}{\mathrm{v}}\)

Question 27.
Relation between force of attraction and distance between two objects is …………………
A) F ∝ \(\frac{1}{\mathrm{R}}\)
B) F ∝ \(\frac{1}{\mathrm{R}^{2}}\)
C) F ∝ \(\frac{1}{\mathrm{R}^{3}}\)
D) F ∝R
Answer:
B) F ∝ \(\frac{1}{\mathrm{R}^{2}}\)

Question 28.
According to universal gravitational law, F =
A) \(\frac{\mathrm{GMm}}{\mathrm{R}^{2}}\)
B) \(\frac{\mathrm{GMm}^{2}}{\mathrm{R}^{2}}\)
C) \(\frac{\mathrm{GM}^{2} \mathrm{~m}}{\mathrm{R}^{2}}\)
D) \(\frac{\mathrm{GMm}}{\mathrm{R}^{3}}\)
Answer:
A) \(\frac{\mathrm{GMm}}{\mathrm{R}^{2}}\)

Question 29.
Relation between time period of a satellite and radius of the planet ………………….
A) T² ∝ R³
B) T ∝ R²
C) T² ∝ R²
D) T³ ∝ R³
Answer:
A) T² ∝ R³

Question 30.
For a vertically projected body, a =
A) + g
B) g²
C) – g
D) None of these
Answer:
C) – g

Question 31.
Force F = ………………….
A) ma²
B) m²a
C) ma
D) m³a²
Answer:
C) ma

Question 32.
For a freely falling body, a = ……………….
A) – g
B) + g²
C) + g³
D) + g
Answer:
D) + g

Question 33.
Which of the following statement is true ?
Statement 1 : Velocity and acceleration of a body in a uniform circular motion are perpendicular to each other.
Statement 2 : The direction of the acceleration of a body in uniform circular motion is always towards its centre.
A) 1
B) 2
C) 1 and 2
D) None
Answer:
C) 1 and 2

Question 34.
Assessment (A) : The net force which change only the direction of the velocity of a body is called centripetal force.
Reason (R) : Centripetal force exists only in uniform circular motion.
A) A and R are true
B) A and R are false
C) A is true but R is false
D) A is false but R is true
Answer:
A) A and R are true

Question 35.
Which of the following is true ?
1) Earth attracts moon and it is gravitational.
2) The gravitational force acts as a centripetal force and makes the moon revolve around the earth in uniform circular motion.
A) 1
B) 2
C) 1 and 2
D) None
Answer:
D) None

Question 36.
1) Force of gravitation acts between any two bodies in the universe.
2) Force of gravitation acts between objects nearer to earth and earth only.
3) F_gravity = G\(\frac{\mathbf{M}_{1} \mathbf{M}_{2}}{\mathbf{d}^{2}}\)
4) G = 6.67 x 10^-11 Nm² Kg^-2
The wrong statement in the above is
A) 1
B) 2
C) 3
D) 2 and 4
Answer:
B) 2

Question 37.
A body has constant speed while rotating in a circular path. Its direction of velocity
A) constant
B) changes
C) A or B
D) 0
Answer:
B) changes

Question 38.

If ΔV is decreases, then the path of the body is
A) in circular motion
B) in polygon motion
C) in spherical motion
D) none
Answer:
A) in circular motion

Question 39.
Once while Sir Isaac Newton was sitting under a tree, an apple fell to the ground. Then some questions arose in his mind. Which questions would be those ?
a) Why did the apple fall to the ground ?
b) Does the apple eatable ?
c) What is the colour of the apple ?
d) What makes the apple to move ?
A) a
B) b and c
C) a and d
D) All
Answer:
C) a and d

Question 40.
What will happen if the distance of a body from the centre of the earth increases ?
A) Force of gravity increases
B) Force of gravity decreases
C) Force of gravity does not change
D) None
Answer:
B) Force of gravity decreases

Question 41.
If there is an attraction force between all objects why do a man not feel himself gravitating towards massive building ?
A) The attraction force between man and earth is greater than that of man and a building.
B) The attraction force between man and earth is less than that of man and a building.
C) The attraction force between man and earth is equal to attraction force between man and a building.
D) None
Answer:
A) The attraction force between man and earth is greater than that of man and a building.

Question 42.
An apple falls because of the gravitational attraction of earth. The gravitational attraction of apple on the earth is …………………. to gravitational force of attraction of earth on the apple.
A) greater than
B) less than
C) equal
D) greater than or equal
Answer:
C) equal

Question 43.
The direction of “g” is ………………….
A) towards sky
B) towards earth
C) horizontal to the earth
D) no direction
Answer:
B) towards earth

Question 44.
If there is no gravity your weight becomes
A) equal to your mass
B) zero
C) more than your mass
D) less than your mass
Answer:
B) zero

Question 45.

What will happen to the scale ?
a) It will fall down.
b) It will not fall down.
A) a
B) b
C) a or b
D) we cannot say
Answer:
B) b

Question 46.
When do you feel weightlessness ?
A) While climbing a tree.
B) While falling freely from a tree.
C) While walking on a road.
D) While running on a sand.
Answer:
B) While falling freely from a tree.

Question 47.
If a paper and a book are dropped from same height at a time, they will reach the ground at same time
A) if their masses are equal
B) if there were no air resistance
C) if there is no gravitation
D) not possible
Answer:
B) if there were no air resistance

Question 48.
The gravitational force of attraction between two bodies is F₁. If the mass of each body is doubled and the distance between them is halved then the gravitational force between them is F₂. Then
A) F₁ = F₂
B) F₂ = 4F₁
C) F₂ = 8F₁
D) F₂ = 16F₁
Answer:
D) F₂ = 16F₁

Question 49.
Weight of a body on the surface of the earth is W. Then weight of the same body on the surface of a planet whose mass is double that of the earth and radius thrice that of the earth is
A) \(\frac{9 \mathrm{~W}}{2}\)
B) 18 W
C) \(\frac{2 \mathrm{~W}}{3}\)
D) \(\frac{2 \mathrm{~W}}{9}\)
Answer:
D) \(\frac{2 \mathrm{~W}}{9}\)

Question 50.
Take an electric motor and fix a disc to the shaft of the electric motor. Place a small wooden block and switch on the motor. Wooden block speed is constant. The path of the wooden block is
A) linear
B) circular
C) uniform circular
D) zig zag
Answer:
C) uniform circular

Question 51.
The apparatus to measure weight of a body is
A) simple balance
B) spring balance
C) electronic balance
D) above all
Answer:
B) spring balance

Question 52.
The time period of a satellite (T) moving around the earth surface depends on
A) mass of the satellite
B) mass of the earth
C) radius of the satellite
D) radius of the earth
Answer:
D) radius of the earth

Question 53.
Weight of a freely falling body is
A) equal to ‘g’
B) equal to ‘mg’
C) zero
D) equal to ‘mg + G’
Answer:
C) zero

Question 54.
The acceleration produced due to gravitational force of the earth near the surface, is called ……………………
A) acceleration due to gravity
B) retardation
C) deceleration
D) acceleration due to object
Answer:
A) acceleration due to gravity

Question 55.
The force due to gravity upon an object is known as its ………………
A) frictional force
B) gravitational force
C) weight force
D) both B & C
Answer:
D) both B & C

Question 56.
The value of universal gravitational constant is found by ………………….
A) Henry Cavendish
B) Berzelius
C) Avagadro
D) Boyle
Answer:
A) Henry Cavendish

Question 57.
Acceleration of moon towards earth is
A) 0.27 cm/s²
B)1.63 m/s²
C) 9.8 m/s²
D) 27.4 m/s²
Answer:
A) 0.27 cm/s²

Question 58.
Acceleration of bodies on earth surface is
A) 981 m/s²
B) 981 cm/s²
C) 9.81 cm/s²
D) 0.98 cm/s²
Answer:
B) 981 cm/s²

Question 59.
Radius of earth is …………………..
A) 6.4 × 10⁶ km
B) 6.4 × 10⁶ m
C) 6.4 × 10⁶ cm
D) 6.4 × 10⁶ mm
Answer:
B) 6.4 × 10⁶ m

Question 60.
Time period of moon around the earth
A) 2.73 days
B) 27.3 days
C) 273 days
D) 2730 days
Answer:
B) 27.3 days

Question 61.
Universal gravitational constant G =
A) 6.67 × 10^-11 Nm²kg^-2
B) 6.67 × 10^-11 N²m²kg^-2
C) 6.67 × 10^-11 N²mkg^-2
D) 6.67 × 10^-11 Nm²kg²
Answer:
A) 6.67 × 10^-11 Nm²kg^-2

Question 62.
Mass of earth is
A) 6 × 10²² kg
B) 6 × 10²⁴ kg
C) 6 × 10²⁰ kg
D) 6 × 10²⁶ kg
Answer:
B) 6 × 10²⁴ kg

Question 63.
Distance of moon from the centre of earth is ………………….. cm.
A) 3.844 × 10¹⁰
B) 3.844 × 10⁶
C) 3.844 × 10⁵
D) 3.844 × 10⁴
Answer:
A) 3.844 × 10¹⁰

Question 64.
F_C \(\frac{\mathbf{m v}^{2}}{\mathbf{R}}\) is given. Here what is v ?
A) speed of a particle
B) weight of a particle
C) velocity of a particle
D) momentum of a particle
Answer:
C) velocity of a particle

Question 65.

• Set A are the equations of uniform accelerated motion.
• Set B are the equations of a free fall body. Then a & b are

A) v = -gt, v² = -2gh
B) v = gt, v² = 2.gh
C) v = g – t, v² – g² = 2h
D) A or B
Answer:
B) v = gt, v² = 2.gh

Question 66.
If 1 kg body weights 1.2 N and 2 kg body weights 2.4 N on a planet. Then the acceleration due to gravity on that planet is
A) 9.8 m/s²
B) 2 m/s²
C) 2.1 m/s
D) 1.2 m/s²
Answer:
D) 1.2 m/s²

Question 67.
On observing the given figure, tell the theory explained by

A) Rutherford
B) Newton
C) Bohr
D) None
Answer:
B) Newton

Question 68.
Name of the theory explained in the above figure.
A) Acceleration
B) Universal law of Gravitation
C) Direction of ‘g’
D) None
Answer:
B) Universal law of Gravitation

Question 69.

Draw the change in velocity in this diagram.

Answer:

Question 70.

A body in the uniform circular motion then the parts 1 and 2 represents
A) Time, Velocity
B) Speed, Velocity
C) Velocity, Acceleration
D) Acceleration, Velocity
Answer:
C) Velocity, Acceleration

Question 71.
Correct position of the centre of gravity located to the given object.

Answer:

Question 72.
Weight vector to the given diagram is


Answer:

Question 73.
The attraction force between two masses of 400 kg and 800 kg are with the distance of 400 meters apart is
A) G
B) 2G
C) G²
D) \(\frac{\mathrm{G}}{2}\)
Answer:
B) 2G

Question 74.
A body is projected vertically up. The distance covered in its last second of upward motion if g = 10 m/s² is
A) 10 m
B) 2 m
C) 5 m
D) 0 m
Answer:
C) 5 m

Question 75.
The time taken, by the body projected vertically up with a speed of 20 m/s to return back to the ground is (g = 10 m/s²)
A) 4 sec
B) 2 sec
C) 40 sec
D) 20 sec
Answer:
A) 4 sec

Question 76.
Which of the following is easier to carry ?
A) Two buckets with same amount of water with both hands
B) One bucket with water with one hand
C) Both A or B
D) Two buckets with different amount of water with both hands
Answer:
A) Two buckets with same amount of water with both hands

Question 77.
A person sitting in a satellite feels weightlessness because
A) the earth does not attract the objects in a satellite.
B) the normal force by the chair on the person balances the earth’s attraction.
C) the normal force is zero.
D) the person in satellite is not accelerated.
Answer:
C) the normal force is zero.

Question 78.
From the top of a building 9 m high, water drops are falling at equal intervals of time, such that when the first drop reaches the ground, the fourth drop is just ready to fall. The distances between the successive drops in meters at that instance is
A) 1, 3, 5
B) 5, 3, 1
C) 1, 4, 9
D) 9, 4, 1
Answer:
B) 5, 3, 1

Question 79.
Weight of 3 kg body is
A) 3 N
B) 3.2 N
C) 29.4 N
D) 19.6 N
Answer:
C) 29.4 N

Question 80.
Gravitational force between two bodies exists
A) when they are in contact only
B) when they are not in contact only
C) any of the above two cases
D) none of these
Answer:
C) any of the above two cases

Question 81.
When a stone moves up, its speed ……………………..
A) increases
B) decreases
C) does not change
D) none of these
Answer:
B) decreases

Question 82.
When a body is freely suspended, the weight is evidenced by ………………………
A) gravitational force
B) normal force
C) tension
D) none of these
Answer:
C) tension

Question 83.
When a body falls freely then it experiences …………………….
A) weight
B) mass
C) weightlessness
D) none of these
Answer:
C) weightlessness

Question 84.
Gravitational force between any two bodies is always ………………… type only.
A) attractive
B) repulsive
C) both
D) none of these
Answer:
A) attractive

Question 85.
The time period of a satellite depends on the …………………. of the planet.
A) diameter
B) radius
C) mass of satellite
D) both A & B
Answer:
D) both A & B

Question 86.
In uniform circular motion, which of the following is/are correct
i) Net force can change only the direction of the velocity of the body
ii) Net force is always directed towards the centre
iii) Net force is called centripetal force
A) i, ii
B) ii, iii
C) i, iii
D) i, ii, iii
Answer:
D) i, ii, iii

Question 87.
The direction of acceleration in uniform circular motion is
A) Tangential
B) Towards centre
C) Away from centre
D) No direction
Answer:
B) Towards centre

Question 88.
When we move away from the surface of the earth, the acceleration due to gravity value
A) Decreases
B)Increases
C) Remains the same
D) Zero
Answer:
A) Decreases

Question 89.
Assertion (A) : weight of an object is less on moon then earth
Reason (R): earth is heavier than moon
A) Both A and R are correct, R is the correct explanation of A
B) Both A and R are correct, R is not the correct explanation of A
C) A is correct, R is not correct
D) A is not correct, R is correct
Answer:
B) Both A and R are correct, R is not the correct explanation of A

Question 90.
Correct order of following options to make a meaningful experiment is
P) Suspend the object from one point, draw vertical line
Q) Centre of gravity lies where two lines intersect
R) Take a India map made of steel
S) Suspend the object from some other point, draw vertical line
A) P, Q, R, S
B) R, S, P, Q
C) R, P, S, Q
D) Q, R, P, S
Answer:
C) R, P, S, Q

Question 91.
What is initial velocity of freely falling body ?
A) 9.8 m/s
B) 8.9 m/s
C) 0 m/s
D) 10 m/s
Answer:
C) 0 m/s

Question 92.
What is the direction of acceleration due to gravity ?
A) Always downwards
B) Always upwards
C) Some times downwards and some times upwards
D) In the direction of object motion
Answer:
A) Always downwards

Question 93.
Assertion : 10kg body weight 98N Reason : weight W – m$
A) Both A and R are correct and R support A
B) Both A and R are correct and R does not support A
C) A correct, R incorrect
D) A in correct, R – correct
Answer:
A) Both A and R are correct and R support A

Question 94.
When a stone and a leaf were dropped from same height in your classroom, then the observation is
A) Both will reach the ground in same time
B) Because of air resistance stone will reach the ground first.
C) Leaf will reach the ground first
D) Both will not reach the ground
Answer:
B) Because of air resistance stone will reach the ground first.

Practice the AP 9th Class Physical Science Bits with Answers Chapter 9 Floating Bodies on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 9th Class Physical Science Bits 9th Lesson Floating Bodies with Answers

Question 1.
Density is defined as
A) mass/litre
B) mass/volume
C) mass/area
D) mass/cross section
Answer:
B) mass/volume

Question 2.
Unit of density
A) kg/cm³
B) g/m³
C) kg/m³
D) m³/kg
Answer:
C) kg/m³

Question 3.
An object floats on the surface of a liquid when
A) the density of the object is more than the density of liquid
B) the density of the object is less than the density of the liquid
C) weight of the object is more than the weight of the liquid
D) weight of the object is less than the weight of the liquid
Answer:
B) the density of the object is less than the density of the liquid

Question 4.
Relative density of an object =
A) Density of the object/density of water
B) Density of water/density of the object
C) Weight of the object/weight of the water
D) Volume of the object/volume of the water
Answer:
A) Density of the object/density of water

Question 5.
Lactometer works on the principle of
A) density
B) relative density
C) buoyancy
D) volume
Answer:
B) relative density

Question 6.
The objects with relative density greater than 1 ………………… water.
A) floats on
B) sinks in
C) suspends in
D) can’t say
Answer:
D) can’t say

Question 7.
At normal atmospheric pressure the height of the mercury column in barometer is
A) 76 cm
B) 7.6 cm
C) 76 mm
D) 100 cm
Answer:
A) 76 cm

Question 8.
The value of one atmospheric pressure is
A) 1.01 × 10³ N/m²
B) 1.01 × 10⁴ N/m²
C) 1.01 × 10⁶N/m²
D) 1.01 × 10⁵ N/m²
Answer:
D) 1.01 × 10⁵ N/m²

Question 9.
Unit of atmospheric pressure is
A) Pascal
B) N/m²
C) A or B
D) None
Answer:
C) A or B

Question 10.
Any object immersed in a water experiences an upward force called
A) gravitation
B) buoyancy
C) pressure
D) density
Answer:
B) buoyancy

Question 11.
Hydraulic jack works on the principle of
A) Archimedes’ principle
B) Buoyancy
C) Pascal’s principle
D) Air pressure
Answer:
C) Pascal’s principle

Question 12.
Mass per unit volume is known as ……………..
A) density
B) relative density
C) weight
D) pressure
Answer:
A) density

Question 13.
Unit of density in MKS system = ……………….
A) g/cm³
B) kg/m³
C) g/mm³
D) kg/km³
Answer:
B) kg/m³

Question 14.
Relative density of an object = …………………
A) \(\frac{\text { density of water }}{\text { density of object }}\)
B) \(\frac{\text { density of object }}{\text { density of water }}\)
C) density of object × density of water
D) none of these
Answer:
B) \(\frac{\text { density of object }}{\text { density of water }}\)

Question 15.
Relative density of a liquid = ……………………

Answer:
C) \(\frac{\text { weight of the liquid }}{\text { weight of same volume of water }}\)

Question 16.
Units of relative density …………………
A) g/cm³
B) kg/m³
C) kg/cm³
D) no units
Answer:
D) no units

Question 17.
Lactometer is used to determine the ……………..
A) purity of water
B) purity of milk
C) purity of sugar
D) purity of oil
Answer:
B) purity of milk

Question 18.
The principle involved in working of a lactometer is …………………
A) density
B) volume
C) relative density
D) pressure
Answer:
C) relative density

Question 19.
The effective density of a mixture of two liquids of densities ρ₁ and ρ₂ when they are taken with same masses …………………
A) \(\frac{1}{2}\) (ρ₁ + ρ₂)
B) \(\frac{2 \rho_{1} \rho_{2}}{\rho_{1}+\rho_{2}}\)
C) \(\frac{2 \rho_{1} \rho_{2}}{\rho_{1}-\rho_{2}}\)
D) \(\frac{1}{2}\) (ρ₁ – ρ₂)
Answer:
B) \(\frac{2 \rho_{1} \rho_{2}}{\rho_{1}+\rho_{2}}\)

Question 20.
The effective density of a mixture of two liquids of densities ρ₁ and ρ₂, when they are taken with same volumes is ………………
A) \(\frac{1}{2}\) (ρ₁ + ρ₂)
B) \(\frac{2 \rho_{1} \rho_{2}}{\rho_{1}-\rho_{2}}\)
C) \(\frac{1}{2}\) (ρ₁ – ρ₂)
D) B) \(\frac{2 \rho_{1} \rho_{2}}{\rho_{1}+\rho_{2}}\)
Answer:
A) \(\frac{1}{2}\) (ρ₁ + ρ₂)

Question 21.
Density of any liquid can be determined by using …………………..
A) hydrometer
B) densitometer
C) hygrometer
D) Both A & B
Answer:
D) Both A & B

Question 22.
The relative density of an object is greater than 1, then the object …………………. in water.
A) floats
B) sinks
C) both A and B
D) none of these
Answer:
B) sinks

Question 23.
The upward pressure acting on a body immersed in water is known as ……………….
A) tension
B) normal force
C) buoyancy
D) thurst
Answer:
C) buoyancy

Question 24.
1 atmosphere = ………………. N/m².
A) 1.01 × 10⁵
B) 1.01 × 10³
C) 1.01 × 10⁷
D) 1.01 × 10⁷
Answer:
A) 1.01 × 10⁵

Question 25.
Density of mercury = ………………….
A) 13.6 g/cc
B) 13.6 g/m³
C) 13.6 g/mm³
D) 13.6 kg/m³
Answer:
B) 13.6 g/m³

Question 26.
Pressure at a depth ‘h’ in a liquid is ………………
A) P = P_o + hρg
B) P = P_o – hρg
C) P_o = P + hρg
D) P_o = P – hρg
Answer:
A) P = P_o + hρg

Question 27.
In a bramah press, force acting on the right piston is …………………
A) F₂ = \(\frac{\mathrm{A}_{1} \times \mathrm{F}_{1}}{\mathrm{~A}_{2}}\)
B) F₂ = \(\frac{\mathrm{F}_{1} \times \mathrm{A}_{2}}{\mathrm{~A}_{1}}\)
C) F₂ = \(\frac{A_{2}}{F_{1} \times A_{1}}\)
D) F₂ = \(\frac{\mathrm{A}_{1}}{\mathrm{~F}_{1} \times \mathrm{A}_{2}}\)
Answer:
B) F₂ = \(\frac{\mathrm{F}_{1} \times \mathrm{A}_{2}}{\mathrm{~A}_{1}}\)

Question 28.
When a body is immersed in a fluid, the force of buoyancy is equal to the ……………
A) volume of fluid displaced
B) pressure of fluid displaced
C) density of fluid displaced
D) weight of fluid displaced
Answer:
D) weight of fluid displaced

Question 29.
Relative density of an object is less than 1 then it ………………..
A) floats in water
B) sinks in water
C) both
D) none of these
Answer:
B) sinks in water

Question 30.
Height of mercury column is ………………..
A) 76 m
B) 76 cm
C) 76 mm
D) Both B & C
Answer:
D) Both B & C

Question 31.
Atmospheric pressure P_o =
A) hρg
B) \(\frac{\mathrm{h} \rho}{\mathrm{g}}\)
C) \(\frac{\mathrm{hg}}{\mathrm{P}}\)
D) \(\frac{\rho g}{h}\)
Answer:
A) hρg

Question 32.
Which of the following sinks in water ?
A) wooden block
B) piece of wax
C) glass marble
D) plastic ball
Answer:
C) glass marble

Question 33.
If we weigh a piece of iron and a piece of wood of same size, iron will weigh more. The reason is
A) density of iron is less than the density of wood
B) weight of iron is more than the weight of wood
C) area of iron is more than the area of wood
D) density of iron is more than the density of wood
Answer:
D) density of iron is more than the density of wood

Question 34.
Force of buoyancy is equal to the ……………….. of the object.
A) apparent loss of volume
B) apparent loss of density
C) apparent loss of pressure
D) apparent loss of weight
Answer:
D) apparent loss of weight

Question 35.
Atmospheric pressure can be measured by using
A) lactometer
B) hydrometer
C) barometer
D) hygrometer
Answer:
C) barometer

Question 36.
Adjacent experiment was done by ancient Greek Scientist.

A) Pascal
B) Archimedes
C) Both of them
D) None
Answer:
B) Archimedes

Question 37.
Name of the arrangement given in the figure.

A) Pascal
B) Archimedes
C) Bramah press
D) Hydralic jack
Answer:
C) Bramah press

Question 38.
Name of the set up given in the figure.

A) Pascal
B) Archimedes
C) Bramah press
D) Hydralic jack
Answer:
D) Hydralic jack

Question 39.
Kerosene ………………. water.
A) floats on
B) sinks in
C) suspends in
D) can’t say
Answer:
A) floats on

Question 40.
Ships are made based on the principle of ………………….
A) pressure
B) volume
C) density
D) buoyancy
Answer:
D) buoyancy

Question 41.
Hydraulic jacks works on …………………. principle.
A) Archimedes
B) Pascal
C) Berzelius
D) Boyle
Answer:
B) Pascal

Question 42.
One pascal equal to
A) 1.01 x 10⁵ Nm^-2
B) 1.01 x 10^-5 Nm^-2
C) 1 Nm^-2
D) 76 Nm^-2
Answer:
C) 1 Nm^-2

Question 43.
The instrument used to test purity of milk is
A) Barometer
B) Hydrometer
C) Potentiometer
D) Lactometer
Answer:
D) Lactometer

Question 44.
A solid sphere has a radius of 2 cm and a mass of 0.05 kg. What is the relative density of the sphere………………….?
A) 1.39
B) 1.39 kg/m³
C) 1.49
D) 1.46 kg/m³
Answer:
C) 1.49

Question 45.
Which of the following law denotes Buoyancy ?
A) Pascal’s Law
B) Archimedes Law
C) Boyl’s Law
D) Newton’s Law
Answer:
B) Archimedes Law

Question 46.
What happens if water is mixed with milk?
A) The density of the mixture is less than the density of milk
B) The density of the mixture is more than the density of milk
C) The volume of the mixture is more than the volume of milk
D) The volume of the mixture is less than the volume of milk
Answer:
B) The density of the mixture is more than the density of milk

Question 47.
Density : \(\frac{\mathbf{k g}}{\mathbf{m}^{3}}\) : :relative density : ………………
A) \(\frac{\mathrm{gm}}{\mathrm{cm}^{3}}\)
B) \(\frac{\mathrm{N}}{\mathrm{m}^{2}}\)
C) \(\frac{\text { pascal }}{\mathrm{m}^{3}}\)
D) No units
Answer:
D) No units

Question 48.
The instrument which is used to test whether water is added to milk or not is
A) Barometer
B) Lactometer
C) Hydrometer
D) Thermometer
Answer:
B) Lactometer

Question 49.
Find the odd one out regarding the construction of hydraulic jackA) Pistons must be frictionless
B) Pistons must be leak proof
C) Pistons must be of same area
D) Fluid inside the jack must be incompressible
Answer:
C) Pistons must be of same area

Andhra Pradesh SCERT AP State Board Syllabus 8th Class Biology Important Bits with Answers in English and Telugu Medium are part of AP Board 8th Class Textbook Solutions.

Students can also read AP Board 8th Class Biology Solutions for board exams.

AP State Syllabus 8th Class Biology Important Bits with Answers in English and Telugu

8th Class Biology Bits in English

• Chapter 1 What is Science? Bits
• Chapter 2 Cell: The Basic Unit of Life Bits
• Chapter 3 Story of Microorganisms 1 Bits
• Chapter 4 Reproduction in Animals Bits
• Chapter 5 Attaining the Age of Adolescence Bits
• Chapter 6 Biodiversity and its Conservation Bits
• Chapter 7 Different Ecosystems Bits
• Chapter 8 Production and Management of Food From Plants Bits
• Chapter 9 Production and Management of Food From Animals Bits
• Chapter 10 Not For Drinking-Not For Breathing Bits
• Chapter 11 Why Do We Fall Ill Bits

8th Class Biology Bits in Telugu

• Chapter 1 విజ్ఞానశాస్త్రం అంటే ఏమిటి? Bits
• Chapter 2 కణం – జీవుల మౌళిక ప్రమాణం Bits
• Chapter 3 సూక్ష్మజీవుల ప్రపంచం 1 Bits
• Chapter 3 సూక్ష్మజీవుల ప్రపంచం 2 Bits
• Chapter 4 జంతువులలో ప్రత్యుత్పత్తి Bits
• Chapter 5 కౌమార దశ Bits
• Chapter 6 జీవ వైవిధ్యం – సంరక్షణ Bits
• Chapter 7 వివిధ ఆవరణ వ్యవస్థలు Bits
• Chapter 8 మొక్కల నుండి ఆహారోత్పత్తి Bits
• Chapter 9 జంతువుల నుండి ఆహారోత్పత్తి Bits
• Chapter 10 పీల్చలేము – తాగలేము Bits
• Chapter 11 మనకు అనారోగ్యం ఎందుకు కలుగుతుంది? Bits

AP State Syllabus Bits with Answers

Practice the AP 10th Class Maths Bits with Answers Chapter 1 Real Numbers on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 10th Class Maths Bits 1st Lesson Real Numbers with Answers

Question 1.
In the rational form of a terminating decimal number prime factor of the denominator is ………………..
A) only 2
B) only 5
C) 2 or 5 only
D) any prime
Answer:
C) 2 or 5 only

Question 2.
log₁₀2 + log₁₀5 value = ……………….
A) 1
B) 2
C) 5
D) 10
Answer:
A) 1

Question 3.
If P₁ and P₂ are two odd prime numbers such that P₁ > P₂, then P₁² -P₂² is ……………..
A) an even number
B) an odd number
C) a prime number
D) an odd prime number
Answer:
A) an even number

Question 4.
The HCF of two consecutive natural numbers is
A) 1
B) 2
C) 3
D) 4
Answer:
A) 1

Question 5.
The fundamental theorem of arithmetic is applicable to
A) 4
B) 3
C) 2
D) 1
Answer:
A) 4

Question 6.
The last digit of 6⁵⁰ is ………………..
A) 1
B) 6
C) 2
D) 3
Answer:
B) 6

Question 7.
A rational number that equals to 2.\(\overline{6}\) is
A) \(\frac{7}{3}\)
B) \(\frac{8}{3}\)
C) \(\frac{16}{7}\)
D) \(\frac{17}{7}\)
Answer:
B) \(\frac{8}{3}\)

Question 8.
The value of log₂₅ 5 = …………………
A) \(\frac{1}{2}\)
B) 2
C) 5
D) 25
Answer:
A) \(\frac{1}{2}\)

Question 9.
The value of log_√2 64 is ………………..
A) -6
B) 12
C) 6
D) 8
Answer:
B) 12

Question 10.
Which is the three digit number divisible by 7 ?
A) 100
B) 133
C) 137
D) 143
Answer:
B) 133

Question 11.
Which one of the following rational numbers have non-terminating repeating decimal expansion ?
A) \(\frac{31}{3125}\)
B) \(\frac{71}{512}\)
C) \(\frac{23}{200}\)
D) None of these
Answer:
D) None of these

Question 12.
Logarithmic form of \(\sqrt[3]{8}\) = 2 is
A) log₈ 2 = \(\frac{1}{3}\)
B) log₂ 8 = \(\frac{1}{3}\)
C) \(\log _{\frac{1}{3}}\) 8 = 2
D) \(\log _{\frac{1}{3}}\) 2 = 0
Answer:
A) log₈ 2 = \(\frac{1}{3}\)

Question 13.
The relation a . (b . c) = (a . b). c is
A) distributive law
B) associative law
C) commutative law
D) closure law
Answer:
A) distributive law

Question 14.
The HCF of 1.2 and 0.12 is
A) 1.2
B) 12
C) 0.12
D) 120
Answer:
C) 0.12

Question 15.
The value of log₃ 243 =
A) 5
B) 6
C) 4
D) 8
Answer:
A) 5

Question 16.
0.10110111011110 …………….. is
A) an integer
B) a rational number
C) an irrational number
D) a natural number
Answer:
C) an irrational number

Question 17.
The LCM of the numbers 2⁷ × 3⁴ × 7 and 2³ × 3⁴ × 11 is
A) 2³ × 3⁴
B) 2⁷ × 3⁴
C) 2⁷ × 3⁴ × 7 × 11
D) 2³ × 3⁴ × 7 × 11
Answer:
C) 2⁷ × 3⁴ × 7 × 11

Question 18.
The number of rational numbers exist between any two distinct rational numbers is
A) 0
B) 1
C) 2
D) infinite
Answer:
D) infinite

Question 19.
The prime factorization of 163800 is
A) 2² × 3³ × 5⁵ × 7 × 13
B) 2³ × 3² × 5² × 7 × 13
C) 2³ × 3² × 5⁵ × 7 × 13
D) None
Answer:
B) 2³ × 3² × 5² × 7 × 13

Question 20.
\(\frac{1}{\log _{x} x y}+\frac{1}{\log _{y} x y}\)
A) 0
B) 1
C) -1
D) 2
Answer:
B) 1

Question 21.
If log₁₀3 = 0.4771, then the value of log 15 + log 2 =
A) 47.71
B) 1.4771
C) 4.77
D) 0.4771
Answer:
B) 1.4771

Question 22.
The value of \(\sqrt{\frac{x}{y}+2+\frac{y}{x}}\) =
A) \(\frac{x}{\sqrt{y}}+\frac{\sqrt{y}}{x}\)
B) \(\frac{x}{y}+\frac{y}{x}\)
C) \(\sqrt{\frac{x}{y}}+\sqrt{\frac{y}{x}}\)
D) \(\frac{\sqrt{x}}{y}+\frac{y}{\sqrt{x}}\)
Answer:
C) \(\sqrt{\frac{x}{y}}+\sqrt{\frac{y}{x}}\)

Question 23.
√3 + √5 is a …………………
A) positive rational number
B) negative rational number
C) positive irrational number
D) negative irrational number
Answer:
C) positive irrational number

Question 24.
If a + b = 5, ab = 6, then a³ + b³ =
A) 5
B) 25
C) 35
D) 125
Answer:
C) 35

Question 25.
2 log 3 – 3 log 2 =
A) log 0
B) log 1
C) log (\(\frac{9}{8}\))
D) log (72)
Answer:
C) log (\(\frac{9}{8}\))

Question 26.
log₂ . log₂₅ 5 =
A) 0
B) 1
C) -1
D) \(\frac{1}{2}\)
Answer:
C) -1

Question 27.
If a^x = \(\left(\frac{a}{k}\right)^{y}\) = k^m then \(\frac{1}{x}-\frac{1}{y}\) =
A) 0
B) 1
C) m
D) \(\frac{1}{\mathrm{~m}}\)
Answer:
D) \(\frac{1}{\mathrm{~m}}\)

Question 28.
The H.C.F. of the numbers 3⁷ × 5³ × 2⁴ and 3² × 7⁴ × 2⁸is …………………
A) 2⁴ × 3²
B) 2⁸ × 3⁷ × 5³ × 7⁴
C) 2⁸ × 3⁷
D) 2 × 3 × 5 × 7
Answer:
A) 2⁴ × 3²

Question 29.
The expanded form of log \(\frac{343}{125}\) is …………………
A) 7 (log 5 – log 7)
B) 4 (log 5 – log7)
C) 2 (log 7 – log 5)
D) 3 (log 7 – log 5)
Answer:
D) 3 (log 7 – log 5)

Question 30.
The value of \(\log _{10}^{0.01}\) is ……………….
A) -1
B) -2
C) -10
D) 0.01
Answer:
B) -2

Question 31.
log \(\left[\frac{x+y}{3}\right]\) = \(\frac{1}{2}\) (log x + log y), then the value of \(\frac{x}{y}+\frac{y}{x}\) is ………………….
A) 9
B) 5
C) 7
D) 11
Answer:
C) 7

Question 32.
log₁₀2 = 0.3010 the number of digits in 4²⁰¹⁷is …………….
A) 2015
B) 2016
C) 1215
D) 1214
Answer:
C) 1215

Question 33.
If a = b² = c³ then log_c ab = ………………..
A) \(\frac{9}{2}\)
B) \(\frac{2}{9}\)
C) \(\frac{4}{9}\)
D) \(\frac{1}{3}\)
Answer:
A) \(\frac{9}{2}\)

Question 34.
If x = log₂ 3 and y = log₂ 5, then log₂15 in terms of x and y is
A) x – y
B) x + y
C) xy
D) x + y – 1
Answer:
B) x + y

Question 35.
If a² + b² = c² then log_a(c – b)
+ log_a(c + b) = ………………..
A) -1
B) -2
C) 1
D) 2
Answer:
B) -2

Question 36.
Identify the terminating decimal.
A) \(\frac{2}{3}\)
B) \(\frac{8}{9}\)
C) \(\frac{3}{8}\)
D) \(\frac{1}{7}\)
Answer:
C) \(\frac{3}{8}\)

Question 37.
Number of two digit numbers divisible by 3 is ……………….
A) 10
B) 20
C) 40
D) 30
Answer:
D) 30

Question 38.
log₁₀125 + log₁₀8 =
A) 1
B) 2
C) 3
D) None
Answer:
C) 3

Question 39.
The relation a (b + c) = ab + ac is
A) commutative law
B) associative law
C) distributive law
D) None
Answer:
C) distributive law

Question 40.
If n is a natural number, then 8ⁿ – 3ⁿ is always divisible by ……………..
A) 3
B) 5
C) 8
D) 11
Answer:
B) 5

Question 41.
√P + √Q is ………………….
A) real number
B) irrational number
C) natural number
D) rational number
Answer:
A) real number

Question 42.
\(\sqrt{\frac{a}{b}+\frac{b}{a}-2}\) = …………………
A) \(\sqrt{\frac{a}{b}}-\sqrt{\frac{b}{a}}\)
B) \(\sqrt{\frac{a}{b}}+\sqrt{\frac{b}{a}}\)
C) \(\frac{\mathrm{a}}{\sqrt{\mathrm{b}}}+\frac{\mathrm{b}}{\sqrt{\mathrm{a}}}\)
D) \(\frac{a}{b}+\frac{b}{a}\)
Answer:
A) \(\sqrt{\frac{a}{b}}-\sqrt{\frac{b}{a}}\)

Question 43.
G.C.F. of 12,18 is
A) 36
B) 6
C) 12
D) 18
Answer:
B) 6

Question 44.
The rational number betwen the pair of numbers \(\frac{1}{2}\) and √1 is
Answer:
A) \(\frac{9}{4}\)
B) \(\frac{3}{4}\)
C) \(\frac{5}{4}\)
D) \(\frac{7}{4}\)
Answer:
B) \(\frac{3}{4}\)

Question 45.
The prime factorisation of 729 is
A) 3⁶
B) 3⁵
C) 3⁴
D) 3⁸
Answer:
A) 3⁶

Question 46.
The number of prime factors of 36 is ……………………..
A) 4
B) 3
C) 2
D) 1
Answer:
C) 2

Question 47.
The exponential form of log₁₀0.001 = -3 is …………………..
A) (0.001)¹⁰ = -3
B) (-3)¹⁰ = 0.001
C) (10)³ =-0.001
D) (10)^-3 = 0.001
Answer:
D) (10)^-3 = 0.001

Question 48.
Which of the following is true for an irrational number ?
i) Which can be written in the form of \(\frac{p}{q}\) where p, q ∈ Z, q ≠ 0.
ii) Which cannot be written in the form of \(\frac{p}{q}\) , where p, q ∈ Z, q ≠ 0.
iii) Non – terminating repeating decimals.
iv) Non – terminating, non – repeating decimals.
A) (i), (iii)
B) (ii), (iv)
C) (i) only
D) (iii) only
Answer:
B) (ii), (iv)

Question 49.
The HCF of the polynomials
(x² – 4x + 4) (x + 3) and (x² + 2x – 3) (x – 2) is …………………
A) x + 3
B) x – 2
C) (x + 3) (x – 2)
D) (x + 3) (x – 2)²
Answer:
C) (x + 3) (x – 2)

Question 50.
\(\sqrt{3+\sqrt{5}}\) = ……………….
A) √2 + 12.
B) \(\sqrt{\frac{8}{2}}+\sqrt{\frac{1}{2}}\)
C) \(\sqrt{\frac{7}{2}}-\sqrt{\frac{1}{2}}\)
D) \(\sqrt{\frac{9}{2}}-\sqrt{\frac{3}{2}}\)
Answer:
C) \(\sqrt{\frac{7}{2}}-\sqrt{\frac{1}{2}}\)

Question 51.
The sum of LCM and HCF of two numbers is 1260. If their LCM is 900 more than their HCF, find the product of two numbers.
A) 205400
B) 194400
C) 109440
D) 29590
Answer:
B) 194400

Question 52.
Find the remainder when the square of any prime number greater than 3 is divided by 6.
A) 6
B) 7
C) 9
D) 1
Answer:
D) 1

Question 53.
If HCF (72, q) = 12 then how many values can q take ?
A) 2
B) 1
C) 4
D) 8
Answer:
A) 2

Question 54.
Find the HCF of 120 and 156.
A) 42
B) 12
C) 19
D) 48
Answer:
B) 12

Question 55.
Find the HCF of 432 and 504.
A) 86
B) 72
C) 96
D) 108
Answer:
B) 72

Question 56.
The LCM of two numbers is 1200. Which of the following cannot be their HCF ?
A) 600
B) 500
C) 800
D) 700
Answer:
A) 600

Question 57.
How many prime factors are there in the prime factorization of 240 ?
A) 3
B) 20
C) 25
D) 6
Answer:
A) 3

Question 58.
The largest number among √2, 3√3 and 4√4 is ………………..
A) √2
B) 3√3
C) 4√4
D) all are equal
Answer:
C) 4√4

Question 59.
The expression (x + y)^-1 (x^-1 + y^-1) is the reciprocal of …………………..
A) x + y
B) xy
C) \(\frac{1}{\mathrm{xy}}\)
D) \(\frac{x}{y}\)
Answer:
C) \(\frac{1}{\mathrm{xy}}\)

Question 60.
The greatest possible length of a scale that can be used to measure exactly 3cm,
5cm, 10cm and 90cm is ……………….
A) 40 cm
B) 80 cm
C) 90 cm
D) 60 cm
Answer:
D) 60 cm

Question 61.
If (x -1)² + (y – 2)⁴ + (z – 3)⁶ = 0 then the
value of xyz is ………………..
A) 1
B) 6
C) 14
D) 0
Answer:
B) 6

Question 62.
a^x = b^y = c^z and abc = 1 then \(\frac{1}{x}+\frac{1}{y}+\frac{1}{z}\) = ………………….
A) 0
B) abc
C) a + b + c
D) \(\frac{1}{a}+\frac{1}{b}+\frac{1}{c}\)
Answer:
A) 0

Question 63.
If 0.\(\overline{7}\) = \(\frac{\mathbf{p}}{\mathbf{q}}\) then p + q = ……………………..
A) 16
B) 15
C) 12
D) 14
Answer:
A) 16

Question 64.
For what values of x, 2^x × 5^x ends with 8 or 5 ? ( )
A) 10
B) 8
C) 5
D) None
Answer:
D) None

Question 65.
If 7^{x + 3} = 5^{x + 3} then the value of ‘x’ is ……………………
A) -3
B) 3
C) 2
D) -2
Answer:
A) -3

Question 66.
= …………………
A) 0
B) 1
C) 1
D) \(\frac{1}{2}\)
Answer:
A) 0

Question 67.
If a + b + c = 1 and \(\frac{1}{a}+\frac{1}{b}+\frac{1}{c}\) = 3. where a, b, c are non zero real numbers. Then the value of ab(a + b) + bc (b + c) + ca (a + c) is ………………………..
A) 0
B) 2
C) 1
D) 3
Answer:
A) 0

Question 68.
If \(\sqrt{15-x \sqrt{14}}=\sqrt{8}-\sqrt{7}\) then x = …………………….
A) 1
B) 0
C) 3
D) 4
Answer:
D) 4

Question 69.
If then …………………..
A) T < 1
B) T = 1
C) T > 2
D) 1 < T < 2
Answer:
C) T > 2

Question 70.
If a^x = b^y – c^z and b² = ac then y = ………………….
A) \(\frac{\mathrm{xz}}{\mathrm{x}+2}\)
B) \(\frac{\mathrm{XZ}}{2(\mathrm{x}-\mathrm{z})}\)
C) \(\frac{\mathrm{xz}}{2(\mathrm{z}-\mathrm{x})}\)
D) \(\frac{2 \mathrm{xz}}{(\mathrm{x}+\mathrm{z})}\)
Answer:
D) \(\frac{2 \mathrm{xz}}{(\mathrm{x}+\mathrm{z})}\)

Question 71.
If the ratio of the ages of Mona and Sona is 4:5 and twelve years hence their ages will be in the ratio of 5 : 6, then the age of Sona after 6 years will be …………………
A) 66 years
B) 55 years
C) 67 years
D) 77 years
Answer:
A) 66 years

Question 72.
In a zoo, there are Rabbits and Pigeons. If their heads are 90 and their legs are 224. Then the number of Pigeons in the zoo is ………………….
A) 70
B) 68
C) 72
D) 22
Answer:
B) 68

Question 73.
If x = \(\sqrt{-1+4 \sqrt{3}}\) then x + \(\frac{1}{x}\) = ……………………
A) 4
B) 6
C) 3
D) 2
Answer:
C) 3

Question 74.
The value of \(\frac{1}{2+\sqrt{3}}+\frac{1}{2-\sqrt{3}}\) is ……………………..
A) 3
B) 4
C) 5
D) 1
Answer:
B) 4

Question 75.
If x = \(\frac{2}{3+\sqrt{7}}\) then (x – 3)² = ………………..
A) 1
B) 4
C) 3
D) 8
Answer:
D) 8

Question 76.
If \(\frac{4+3 \sqrt{3}}{2+\sqrt{3}}\) = a + √b then (a, b) = …………………….
A) (12, 1)
B) (-1, 12)
C) (-12, -1)
D) (-12,1)
Answer:
B) (-1, 12)

Question 77.
If \(\frac{\sqrt{7}-\sqrt{3}}{x}=\frac{x}{\sqrt{7}+\sqrt{3}}\) then the value of x = …………………….
A) 11
B) 2
C) 16
D) 12
Answer:
B) 2

Question 78.
If p³ + q³ + r³ then log_pr – q + log_p(r² + qr + q²) ………………..
A) 3
B) 8
C) 9
D) 14
Answer:
A) 3

Question 79.
= …………………..
A) 10.52
B) 1.5
C) 3.5
D) 20.5
Answer:
B) 1.5

Question 80.
\(\frac{1}{\log _{2} \cdot \log _{2} \cdot \log _{2} 16}\) = ………………….
A) 1
B) 5
C) 6
D) 8
Answer:
A) 1

Question 81.
If log(x + y) = log(\(\frac{3 x-3 y}{2}\)) then log x – log y = …………………….
A) log 6
B) log 3
C) log 5
D) log 2
Answer:
C) log 5

Question 82.
If log [latex]\frac{x+y}{3}[/latex] = \(\frac{1}{2}\) [log x + log y] then \(\frac{x}{y}+\frac{y}{x}\) = ………………..
A) 8
B) 7
C) 10
D) 9
Answer:
B) 7

Question 83.
If log₁₀3 = 0.4771, then the value of log 15 + log 2 = ………………….
A) 1.4771
B) 47.71
C) 4.77
D) 0.4771
Answer:
A) 1.4771

Question 84.
Find the value of \(\log _{\frac{4}{3}} \frac{256}{81}\)
A) 1
B) 8
C) 2
D) 4
Answer:
D) 4

Question 85.
(X^a. X^b)^{a – b}(X^b. X^c)^{b – c}(x^c. X^a)^{c – a} = …………………..
A) 0
B) 1
C) ∞
D) 2
Answer:
B) 1

Question 86.
If \(x^{1-\log _{5}^{x}}\) = 0.04 then x = ………………..
A) 5, \(\frac{1}{25}\)
B) \(\frac{1}{5}\), 25
C) 25, 5
D) \(\frac{1}{5}, \frac{1}{25}\)
Answer:
B) \(\frac{1}{5}\), 25

Question 87.
If log₁₀343 = 2.5353, then the least positive integer ‘n’ such that 7ⁿ > 10⁵ is
A) 6
B) 1
C) 4
D) 5
Answer:
A) 6

Question 88.
If x² + y² = 6xy then 2 log(x + y)-log(xy) = …………………
A) log 2
B) 2 log 2
C) 3 log 2
D) 4 log 2
Answer:
C) 3 log 2

Question 89.
\(\frac{4}{9^{\frac{1}{3}}-3^{\frac{1}{3}}+1}=\mathbf{A} \cdot 3^{\frac{1}{3}}\) + B then
A) A = 2
B) A = 3
C) B = 1
D) B = 2
Answer:
C) B = 1

Question 90.
x = 3 + 2√2 then x⁴ + \(\frac{1}{x^{4}}\) = ……………….
A) 1152
B) 1053
C) 1154
D) 1159
Answer:
C) 1154

Question 91.
x = \(\frac{\sqrt{2}+1}{\sqrt{2}-1}\) , y = \(\frac{\sqrt{2}-1}{\sqrt{2}+1}\) then x² – xy + y² = …………………..
A) 33
B) 37
C) 36
D)49
Answer:
A) 33

Question 92.
\(\sqrt[3]{a}+\sqrt[3]{b}+\sqrt[3]{c}\) = 0 then (a + b + c)³ = ……………….
A) 3 abc
B) 9 abc
C) 27 abc
D) 81 abc
Answer:
C) 27 abc

Question 93.
Rationalising factor of \(\sqrt[3]{16}-\sqrt[3]{4}\) + 1 is …………………….
A) \(\sqrt[3]{4}\) + 2
B) \(\sqrt[3]{4}\) – 2
C) \(\sqrt[3]{4}\) + 1
D) \(\sqrt[3]{4}\) – 1
Answer:
C) \(\sqrt[3]{4}\) + 1

Question 94.
then k = ……………………..
A) k = \(\frac{l}{2}\)
B) l = \(\frac{2}{k}\)
C) l = \(\frac{\mathrm{k}}{2}\)
D) K = \(\frac{2}{l}\)
Answer:
B) l = \(\frac{2}{k}\)

Question 95.
A rationalising factor of \(\sqrt[3]{25}+\frac{1}{\sqrt[3]{25}}-1\) is …………………
A) \(5^{\frac{1}{3}}-5^{\frac{1}{3}}\)
B) \(5^{\frac{1}{3}}+5^{\frac{1}{3}}\)
C) \(25^{\frac{1}{3}}+25^{\frac{-1}{3}}\)
D) \(25^{\frac{1}{3}}-25^{\frac{-1}{3}}\)
Answer:
B) \(5^{\frac{1}{3}}+5^{\frac{1}{3}}\)

Question 96.
\(\frac{\sqrt{x^{2}+1}+\sqrt{x^{2}-1}}{\sqrt{x^{2}+1}-\sqrt{x^{2}-1}}\) + \(\frac{\sqrt{x^{2}+1}-\sqrt{x^{2}-1}}{\sqrt{x^{2}+1}+\sqrt{x^{2}-1}}\)
A) 3x²
B) 2x²
C) 2x
D) 4x²
Answer:
B) 2x²

Question 97.
Arithmetic mean of two surds is 5 +9√2 and one of them is 1 + 12√2 then second surd is ……………….
A) 7 + 6√2
B) 9 + 6 √2
C) 10 + 6√2
D) 8 + 6√2
Answer:
B) 9 + 6 √2

Question 98.
\(\frac{1+\sqrt{2}}{3-2 \sqrt{2}}\) = a + b√2 then (a, b) = ……………………
A) (7, 5)
B) (-7, 5)
Q (3, 5)
D) (-7, -5)
Answer:
A) (7, 5)

Question 99.
x = 2√2 + √7 then \(\frac{1}{2}\left(x-\frac{1}{x}\right)\) = …………………
A) √2
B) √7
C) √8
D) 2√7
Answer:
B) √7

Question 100.
If the product of two irrational numbers is rational, then which of the following can be concluded ?
A) The ratio of the greater and the smaller numbers is an integer.
B) The sum of the numbers must be rational.
C) The excess of the greater irrational number over the smaller irrational number must be rational.
D) The sum of the numbers must be irrational
Answer:
D) The sum of the numbers must be irrational

Question 101.
Which of the following is always true?
A) The product of two distinct . irrational numbers is irrational.
B) The rationalising factor of a number is unique.
C) The sum of two distinct irrational numbers is rational.
D) None of these
Answer:
D) None of these

Question 102.
Which of the following pair of numbers is co-prime ?
A) 8 and 14
B) 6 and 35
C) 4 and 12
D) 9 and 19
Answer:
B) 6 and 35

Question 103.
Which of the following is not an irrational number ?
A) √2
B) √9
C) √3
D) √7
Answer:
B) √9

Question 104.
Which of the following is a rational number ?
A) √2
B) π
C) \(\frac{1}{3}\)
D) √3
Answer:
C) \(\frac{1}{3}\)

Question 105.
Which of the following four digit numbers is a perfect square such that the first two digits and the last two digits considered separately also represent perfect squares ?
A) 1681
B) 5462
Q 8214
D) 7210
Answer:
A) 1681

Question 106.
The solution of which equation is an irrational number ?
A) \(\frac{1}{x}=\frac{3}{4}\)
B) x² = \(\frac{49}{20}\)
C) \(\frac{1}{2} x+\frac{1}{5}=\frac{1}{3}\)
D) ² = \(\frac{9}{16}\)
Answer:
B) x² = \(\frac{49}{20}\)

Question 107.
Which of the following is always true?
A) Every irrational number is a surd.
B) Any surd of the form n√a + n√b can be rationalised by a surd of the form n√a -n√b where n√a and n√b are surds.
C) Both (A) and (B)
D) Neither (A) nor (B)
Answer:
D) Neither (A) nor (B)

Question 108.
Among the following a rational number is ………………
A) 1.121212 ……………..
B) 1.23874 ………………
C) 0.23567 ……………….
D) 0.1785 ………………
Answer:
B) 1.23874 ………………

Question 109.
If log₃2 log₃(2^x – 5) log₃(2^x – \(\frac{7}{2}\)) are in A.P then x is
A) an odd positive integer
B) a positive fraction
C) an even positive integer
D) an odd positive integer or even positive integer
Answer:
A) an odd positive integer

Question 110.
If n is an odd natural number, 3²ⁿ + 2²ⁿ is always divisible by ………………
A) 13
B) 15
C) 17
D) 19
Answer:
A) 13

Question 111.
Given that the units digit of A³ and A are the same where A is a single digit natural number. How many possibilities can A assume ?
A) 3
B) 4
C) 5
D) 9
Answer:
C) 5

Question 112.
The remainder of any perfect square divided by 3 is
A) 0
B) 1
C) either (A) or (B)
D) neither (A) nor (B)
Answer:
C) either (A) or (B)

Question 113.
The LCM and HCF of two numbers are equal, then the numbers must be ……………….
A) prime
B) co-prime
C) composite
D) equal
Answer:
D) equal

Question 114.
n² – 1 is divisible by 8, if n is ……………………..
A) an odd number
B) an even number
C) prime number
D) integer
Answer:
A) an odd number

Question 115.
If n is a natural number, then which of the following expression ends with zero ?
A) (3 × 2)ⁿ
B) (5 × 7)ⁿ
C) (9 × 3)ⁿ
D) (2 × 5)ⁿ
Answer:
D) (2 × 5)ⁿ

Question 116.
The decimal expansion of \(\frac{9}{17}\) is …………………….
A) Terminating
B) Non-terminating and non-repeating
C) Non-terminating and repeating
D) Terminating and repeating
Answer:
C) Non-terminating and repeating

Question 117.
If n is any natural number then 6ⁿ – 5ⁿ always ends with …………………
A) 1
B) 5
C) 8
D) 7
Answer:
A) 1

Question 118.
If 6a53435 is divisible by both 5 and 3, then the least possible value of ‘a’ is ……………..
A) 1
B) 0
C) 2
D) 3
Answer:
A) 1

Question 119.
If a = 2 + √3 and b = 2 – √3 then a + b is ………………….
A) Rational
B) Irrational
C) 0
D) Natural
Answer:
B) Irrational

Question 120.
The multiplicative inverse does not exist in the set of ………………..
A) Natural numbers
B) Whole numbers
C) Integers
D) All
Answer:
D) All

Question 121.
Logarithmic form of 10³ = 1000
A) log₁₀¹⁰⁰⁰ = 3
B) log₃¹⁰ = 3
C) log₁₀³ = 3
D) None
Answer:
A) log₁₀¹⁰⁰⁰ = 3

Question 122.
\((\sqrt[m]{\sqrt[n]{a b}})^{\min }\) = ………………..
A) abⁿ
B) ab^m
C) a^mb
D) ab
Answer:
D) ab

Question 123.
If n is a natural number, then 9²ⁿ – 4²ⁿ is always divisible by…………………..
A) 5
B) 13
C) either (A) or (B)
D) neither (A) nor (B)
Answer:
C) either (A) or (B)

Question 124.
N is a natural number such that when ‘N is divided by N’, it leaves remainder a. It can be concluded that ………………….
A) a is a perfect cube
B) a is a perfect square
C) a is a perfect square and cube
D) neither (A) nor (B)
Answer:
A) a is a perfect cube

Question 125.
There is a circular path around a sports field. Anand takes 18 minutes to drive one round of the field while Prakash takes 12 minutes for the same. Suppose they both start at the same point and at the same time and go in the same direc¬tion. After how many minutes will they meet again at the starting point ?
A) 36 minutes
B) 19 minutes
C) 48 minutes
D) 56 minutes
Answer:
A) 36 minutes

Question 126.
A sweet seller has 420 Kaju burfies and 130 Badam burfies. She wants to stock them in such a way that each stock has the same number and they take up the least area of the tray. What is the number of burfies that can be placed in each stock for this purpose ?
A) 15
B) 10
C) 40
D) 45
Answer:
B) 10

Question 127.
In a seminar, the number of participants in English, Mathematics and Science are 36, 60 and 84 respectively. Find the minimum number of rooms required if in each room the same number of participants are to be seated and all of them being in the same subject.
A) 15
B) 28
C) 40
D) 18
Answer:
A) 15

Question 128.
Ramu has two vessels which contain 720 ml and 405 ml of milk respectively. Milk in each vessel is poured into glasses of equal capacity to their brim. Find the minimum number of glasses which can be filled with milk.
A) 25
B) 36
C) 48
D) 65
Answer:
A) 25

Question 129.
A student is ranked 9^th from the top and 38^th from the bottom in a class. The number of students in the class is ………………
A) 46
B) 48
C) 45
D) 49
Answer:
A) 46

Question 130.
In a group of elephants and ducks if the number of legs are 24 more than twice the number of heads, then the number of elephants in the group is …………………
A) 6
B) 12
C) 8
D) 16
Answer:
B) 12

Question 131.
The sum of seven numbers is 235. If the average of the first three numbers is 23 and that of the last three numbers is 42, then the fourth number is ……………….
A) 120
B) 66
C) 40
D) 195
Answer:
C) 40

Question 132.
If a two digits number is divisible by 3 and 4, also the difference between the unit’s digit and the ten’s digit is equal to 4, then the number is ………………..
A) 96
B) 48
C) 72
D) 36
Answer:
B) 48

Question 133.
Complete the missing entries in the following factor tree.

A) 42,21
B) 61, 71
C) 21,46
D) 21,48
Answer:
A) 42,21

Question 134.
Identify the factors of 24.

Answer:

Question 135.
Which of the following may be the value of √2 on the number line

Answer:

Question 136.
Which of the following triangle was √2

Answer:

Question 137.
In between which two parts \(\frac{3}{4}\) can belocated in the number line

Answer:

Practice the AP 9th Class Physical Science Bits with Answers Chapter 5 What is inside the Atom? on a regular basis so that you can attempt exams with utmost confidence.

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

Question 1.
An atom is electrically
A) positive
B) negative
C) neutral
D) no change
Answer:
C) neutral

Question 2.
The smaller particles present inside the atom are called
A) elements
B) protons
C) electrons
D) sub-atomic particles
Answer:
D) sub-atomic particles

Question 3.
The important sub-atomic particles inside the atom are
A) protons
B) neutrons
C) electrons
D) all the above
Answer:
D) all the above

Question 4.
The negatively charged particles are
A) electrons
B) protons
C) neutrons
D) none
Answer:
A) electrons

Question 5.
The positively charged particles are
A) electrons
B) protons
C) neutrons
D) none
Answer:
B) protons

Question 6.
The chargeless particles are
A) electrons
B) protons
C) neutrons
D) none
Answer:
C) neutrons

Question 7.
The charge of alpha particles is
A) positive
B) negative
C) neutral
D) none
Answer:
A) positive

Question 8.
Rutherford’s model is known as
A) plum pudding model
B) nuclear model
C) watermelon model
D) positive model
Answer:
B) nuclear model

Question 9.
The nucleons are
A) protons and electrons
B) electrons and neutrons
C) protons and neutrons
D) neutrons
Answer:
C) protons and neutrons

Question 10.
Rutherford’s model could not explain
A) positivity of the atom
B) negativity of the atom
C) neutrality of the atom
D) stability of the atom
Answer:
D) stability of the atom

Question 11.
According to Neils Bohr’s model, electrons are present in
A) shells
B) nucleus
C) outside the atom
D) cannot found
Answer:
A) shells

Question 12.
Most of the mass of an atom is concentrated in
A) protons
B) electrons
C) neutrons
D) nucleus
Answer:
D) nucleus

Question 13.
n = 2, represents ………………. shell.
A) K
B) L
C) M
D) N
Answer:
B) L

Question 14.
Maximum number of electrons that can be accommodate in a shell is given by the formula
A) 2n
B) n²
C) 2n²
D) 2n³
Answer:
C) 2n²

Question 15.
Maximum number of electrons that can be accommodated in N shell is
A) 2
B) 32
C) 16
D) 18
Answer:
B) 32

Question 16.
The valency of sulphur is
A) 2
B) 6
C) 2 and 6
D) 0
Answer:
C) 2 and 6

Question 17.
The valency of neon is
A) 1
B) 3
C) 2
D) 0
Answer:
D) 0

Question 18.
In im1 Al the number of neutrons are
A) 14
B) 13
C) 27
D) 40
Answer:
A) 14

Question 19.
The number of nucleons is the
A) atomic number
B) mass number
C) number of neutrons
D) number of protons
Answer:
B) mass number

Question 20.
The …………………. isotope is used in the treatment of goitre.
A) isotope of iodine
B) isotope of uranium
C) isotope of cobalt
D) isotope of hydrogen
Answer:
A) isotope of iodine

Question 21.
Which of the following is an example of isotopes ?
A) \({ }_{1}^{1} \mathrm{H},{ }_{1}^{2} \mathrm{H},{ }_{1}^{3} \mathrm{H}\)
B) \({ }_{6}^{12} \mathrm{C},{ }_{6}^{13} \mathrm{C},{ }_{6}^{14} \mathrm{C}\)
C) \({ }_{17}^{35} \mathrm{Cl},{ }_{17}^{37} \mathrm{Cl}\)
D) All the above
Answer:
D) All the above

Question 22.
The mass of neutron is nearly equal to that of ………………….
A) proton
B) electron
C) α – particle
D) β – particle
Answer:
A) proton

Question 23.
According to Thomson, the total ………………… of the atom is uniformly distributed throughout the atom.
A) volume
B) density
C) pressure
D) mass
Answer:
D) mass

Question 24.
Rutherford allowed the alpha particles to pass through ……………………. in his
alpha particles scattering experiment.
A) aluminium foil
B) silver foil
C) copper foil
D) gold foil
Answer:
D) gold foil

Question 25.
Alpha particles do not have …………………
A) electrons
B) protons
C) neutrons
D) none of these
Answer:
A) electrons

Question 26.
Statement – I: Alpha particles consists of 2 protons.
Statement – II : Alpha particles con-sists of 4 neutrons.
A) Both the statements are true.
B) Statement -1 true and Statement – II false.
C) Statement -1 false and Statement – II true.
D) Both the statements are false.
Answer:
A) Both the statements are true.

Question 27.
According to Bohr’s model, electrons revolve around nucleus in …………………
A) orbits
B) shells
C) orbitals
D) both A & B
Answer:
D) both A & B

Question 28.
If n = 3, it represents the ……………….. shell.
A) K
B) L
C) M
D) N
Answer:
C) M

Question 29.
According to Rutherford, the mass of the atom is concentrated at ………………..
A) orbit
B) shell
C) orbital
D) nucleus
Answer:
D) nucleus

Question 30.
Electrons must ……………… energy to move to a higher energy level.
A) absorb
B) emit
C) radiate
D) no change
Answer:
A) absorb

Question 31.
Electrons must ………………. energy to move to a lower energy level.
A) absorb
B) emit
C) radiate
D) both B & C
Answer:
D) both B & C

Question 32.
According to Bohr, while electrons are revolving in …………………..
A) discrete
B) stationary
C) higher energy
D) both A & B
Answer:
D) both A & B

Question 33.
Bohr’s model could not explain the spectra of ……………….
A) Hydrogen
B) He⁺
C) Li²⁺
D) Heavier atoms
Answer:
D) Heavier atoms

Question 34.
The rules for distribution of electrons is given by …………………
A) Bohr
B) Rutherford
C) Bury
D) Both A & C
Answer:
D) Both A & C

Question 35.
Maximum number of electrons that can be accommodated in M – shell is ………………
A) 2
B) 8
C) 18
D) 32
Answer:
C) 18

Question 36.
The electronic structure of oxygen is ………………
A) 2, 4
B) 2, 6
C) 2, 8
D) 2, 8, 2
Answer:
B) 2, 6

Question 37.
The number of electrons present in outer most orbit of an atom is called …………………… electrons.
A) valency
B) paired
C) unpaired
D) love pair
Answer:
A) valency

Question 38.
An outer most shell which has 8 elec-trons is said to possess an ………………. configuration.
A) dublet
B) octet
C) triplet
D) tetralet
Answer:
B) octet

Question 39.
An atom with 8 electrons in its outer most shell is chemically …………………
A) stable
B) unstable
C) both
D) none of these
Answer:
A) stable

Question 40.
Atoms of an element react with other atoms, to achieve ………………….. in their outer most shell.
A) singlet
B) octet
C) triplet
D) tetralet
Answer:
B) octet

Question 41.
An atom can achieve octet by …………………. or of electrons.
A) transfer
B) sharing
C) both A and B
D) none of these
Answer:
C) both A and B

Question 42.
Transfer or sharing of electrons by an atom results in the formation of ……………………. between the atoms.
A) attractive forces
B) chemical bond
C) repulsive force
D) both A & B
Answer:
C) repulsive force

Question 43.
The number of protons in the nucleus of an atom is its …………………
A) atomic number
B) mass number
C) atomic mass
D) atomic volume
Answer:
A) atomic number

Question 44.
The number of nucleons is called ……………….. of the atom.
A) atomic number
B) atomic mass number
C) atomic mass
D) atomic volume
Answer:
B) atomic mass number

Question 45.
Number of neutrons N = ……………….
A) A – Z
B) A + Z
C) A × Z
D) A / Z
Answer:
A) A – Z

Question 46.
Atomic number is denoted by
A) A
B) Z
C) A – Z
D) A + Z
Answer:
B) Z

Question 47.
Mass number is denoted by
A) Z
B) A – Z
C) A
D) A + Z
Answer:
C) A

Question 48.
The elements which have a highest number of known isotopes ……………….. are and ……………..
A) Xenon, Cesium
B) Sodium, Potassium
C) Calcium, Strontium
D) Barium, Radium
Answer:
A) Xenon, Cesium

Question 49.
The isotopes of Uranium is used as fuel in ………………. reactors.
A) Thermal
B) Hydro
C) Wind
D) Nuclear
Answer:
D) Nuclear

Question 50.
The isotope of …………………. is used in treatment of cancer.
A) Iron
B) Sodium
C) Iodine
D) Cobalt
Answer:
D) Cobalt

Question 51.
\({ }_{1}^{2} \mathrm{H}\)is called …………………
A) Hydrogen
B) Deuterium
C) Tritium
D) None of these
Answer:
B) Deuterium

Question 52.
Xenon and cesiums have …………….. known isotopes.
A) 30
B) 32
C) 36
D) 40
Answer:
C) 36

Question 53.
……………….. are not part of nucleus.
A) Protons
B) Electrons
C) Positrons
D) Neutrons
Answer:
B) Electrons

Question 54.
Electron configuration of Neon is ………………..
A) 2
B) 2, 8
C) 2, 8, 8
D) 2, 8, 7
Answer:
B) 2, 8

Question 55.
Match the following.

A) a → 4, b → 1, c → 2, d → 3
B) a→ 3, b → 2, c → 1, d → 4
C) a → 2, b → 3, c → 4, d → 1
D) a → 1, b → 2, c → 3, d → 4
Answer:
A) a → 4, b → 1, c → 2, d → 3

Question 56.
Match the following.

A) a → 2, b → 1, c → 3
B) a → 3, b → 1, c → 2
C) a → 1, b → 2, c → 3
D) a → 2, b → 3, c → 1
Answer:
B) a → 3, b → 1, c → 2

Question 57.
Which of the following is a wrong statement ?
A) Mass of proton was 1836 times greater than that of the electron
B) Proton is represented as P^–
C) Proton repels neutrons
D) Proton is a subatomic particle in an atom
Answer:
B) Proton is represented as P^–

Question 58.
If there are no protons in an atom, the consequences are
A) all atoms possess negative charge.
B) all atoms possess positive charge.
C) all atoms possess neutral charge.
D) above all
Answer:
A) all atoms possess negative charge.

Question 59.
‘X’ is a subatomic particle. It has neither +ve nor -ve. Then ‘X’ is
A) proton
B) positron
C) electron
D) neutron
Answer:
D) neutron

Question 60.
If an α – particle comes closure to a proton, it …………………. proton.
A) attracts
B) repels
C) no change
D) first attracts and then repels
Answer:
B) repels

Question 61.
Electron do not fall in nucleus, because
A) electron do not radiate energy while rotating in discrete orbits.
B) electron radiates energy while rotating in discrete orbits.
C) the size of nucleus is very small to attract the electron.
D) A and C
Answer:
A) electron do not radiate energy while rotating in discrete orbits.

Question 62.
Fluorine atom contains seven electrons in outermost shell, but its valency is ‘1’. Predict the reason.
A) It can loss six electrons from the valency shell.
B) It can loss only one electron from the valency shell.
C) It can gain only one electron.
D) It can gain only seven electrons.
Answer:
B) It can loss only one electron from the valency shell.

Question 63.
According to the electrolysis experiments conducted by …………….., the atoms were acquiring negative charge during the process of electrolysis.
A) Dalta
B) Michael Faraday
C) Rutherford
D) Bohr
Answer:
B) Michael Faraday

Question 64.
Mass of electron is …………….. times less than that of proton.
A) 1200
B) 1836
C) 1830
D) 1870
Answer:
B) 1836

Question 65.
Neutrons were discovered by …………………
A) J.J. Thomson
B) Rutherford
C) Goldstein
D) Chadwick
Answer:
D) Chadwick

Question 66.
The atoms of same element which have same numbers of protons, but have different number of neutrons are called ………………….
A) Isobars
B) Isotopes
C) Isotones
D) Isomers
Answer:
B) Isotopes

Question 67.
Match the following.

A) a → 3, b → 1, c → 2
B) a → 2, b → 1, c → 3
C) a→ 1, b → 2, c → 3
D) a → 3, b → 2, c → 1
Answer:
B) a → 2, b → 1, c → 3

Question 68.

From the table, which of the following is not correct ?
A) Electron has negative charge
B) Neutron has no charge
C) Proton has both mass and charge
D) Mass of the electron is very very less
Answer:
B) Neutron has no charge

Question 69.
Rutherford : ………………. :: JJ Thomson : Watermelon
A) planetary system
B) coconut
C) α – particle
D) big bang
Answer:
A) planetary system

Question 70.

In the figure …………………. has more energy.
A) K – shell
B) L – shell
C) M – shell
D) All are equal
Answer:
C) M – shell

Question 71.

From the given time line, which of the sub-atomic particle discovered at last?
A) proton
B) electron
C) neutron
D) none
Answer:
B) electron

Question 72.
The given atom is
A) He
B) O
C) Ne
D) Ar
Answer:
C) Ne

Question 73.

The common property of the above atoms is
A) same number of shells
B) same atomic number
C) same valency
D) above all
Answer:
C) same valency

Question 74.
Electrons distribution in the given diagram

A) 2, 6
B) 2, 4
C) 2, 2
D) 0, 8
Answer:
B) 2, 4

Question 75.

The outermost orbit in ‘Ne’ is
A) K
B) L
C) M
D) N
Answer:
B) L

Question 76.
From the above table no. of protons in ‘Ar’ is
A) 8
B) 16
C) 18
D) 10
Answer:
C) 18

Question 77.
From the above table valency of ‘Ar’ is
A) 8
B) 2
C) 18
D) 0
Answer:
D) 0

Question 78.

What is the symbol of carbon ?
A) Ca
B) C
C) Cr
D) Cl
Answer:
B) C

Question 79.
From the above table, what is the atomic number of hydrogen ?
A) 1
B) 2
C) 3
D) 0
Answer:
A) 1

Question 80.
From the above table no. of protons Neon is
A) 5
B) 4
C) 6
D) 10
Answer:
D) 10

Question 81.
Which of the sub-atomic particle is not in the hydrogen?
A) proton
B) electron
C) neutron
D) none
Answer:
C) neutron

Question 82.
\({ }_{6}^{14} \mathrm{C},{ }_{6}^{13} \mathrm{C},{ }_{6}^{12} \mathrm{C}\) what are these ?
A) Isotopes
B) Isobars
C) Isotones
D) None
Answer:
A) Isotopes

Question 83.
In \({ }_{6}^{14} \mathrm{C}\), how many neutrons are there ?
A) 6
B) 14
C) 8
D) 20
Answer:
C) 8

Question 84.
Below experiment done by

A) Bohr
B) Thomson
C) Rutherford
D) Hund’s
Answer:
C) Rutherford

Question 85.
Correct labelling of the given diagram is

A) 1 – proton, 2 – neutron, 3 – electron
B) 1 – neutron, 2 – proton, 3 – electron
C) 1 – electron, 2 – neutron, 3 – proton
D) 1 – electron, 2 – proton, 3 – neutron
Answer:
C) 1 – electron, 2 – neutron, 3 – proton

Question 86.
The defect in the diagram is

A) Number of electrons in K – shell
B) Number of shells
C) Nucleus has V charge
D) No defect
Answer:
A) Number of electrons in K – shell

Question 87.
For electron distribution 2, 8, 8, the atomic diagram is

D) None
Answer:

Question 88.
Dallons atomic model is

Answer:

Question 89.
Joseph John Thomson is appreciable because, he found
A) first atom
B) electron
C) proton
D) above all
Answer:
B) electron

Question 90.
Rutherford is appreciable, because he found that
A) Nucleus in the atom
B) Atom has empty space in it
C) Nucleus has a positive charge
D) Above all
Answer:
D) Above all

Question 91.
Which isotope is very useful to treat goitre ?
A) Iodine
B) Sodium
C) Uranium
D) None
Answer:
A) Iodine

Question 92.
Which of the following isotope uses for treatment of Cancer ?
A) Iodine
B) Sodium
C) Cobalt
D) None
Answer:
C) Cobalt

Question 93.
Isotopes are not used in this system.
A) Solving chemical and medical mysteries
B) Investigating the steps of a chemical reaction
C) Medical treatment
D) To pass electricity
Answer:
D) To pass electricity

Question 94.
Carbon dating is related to
A) carbon isotope \(\left({ }_{6}^{14} \mathrm{C}\right)\)
B) fossils
C) A and B
D) neither A nor B
Answer:
C) A and B

Question 95.
Neutrons in gfi \({ }_{8}^{16} \mathrm{O}\) are
A) 8
B) 16
C) 23
D) Zero
Answer:
A) 8

Question 96.
Which of the following is a correct electronic configuration of sodium ?
A) 2, 8
B) 8, 2, 1
C)2, 1, 8
D) 2, 8, 1
Answer:
D) 2, 8, 1

Question 97.
\({ }_{6}^{14} \mathrm{C}\) isotope is used to find
A) age of fossils
B) nature of genes
C) medical treatment
D) above all
Answer:
A) age of fossils

Question 98.
The combining capacity of atoms of an element with the atoms of other element is called its valency. Based on valency the odd one is
A) Hydrogen
B) Chlorine
C) Helium
D) Oxygen
Answer:
C) Helium

Question 99.
Based on scientists and their inventions match Set – I with Set – II:

A) P – y, Q – z, R – x
B) P – y, Q – x, R – z
C) P – x, Q – y, R – z
D) P – z, Q – x, R – y
Answer:
A) P – y, Q – z, R – x

Question 100.
Isotopes are used in the laboratory to investigate the steps of chemical reactions and medical mysteries. An isotope which is used in the treatment of Goitre is
A) Iodine isotope
B) Carbon isotope
C) Cobalt isotope
D) Uranium isotope
Answer:
A) Iodine isotope

Question 101.
Arrangement of electrons in an atom with atomic number (Z) = 5 and valency = 3is
A) 2, 3
B) 1, 1,3
C)2, 1, 2
D) 2, 2, 1
Answer:
A) 2, 3

Question 102.
α-partides scattering experiment helped to detect the existence of the nucleus. The main observation of this experiment is
A) All the alpha particles got deflected.
B) Few no. of alpha particles got deflected.
C) Alpha particles don’t passed . through the gold foil.
D) All the alpha particles passed through the gold foil.
Answer:
B) Few no. of alpha particles got deflected.

Question 103.
α-particles scattering experiment confirms
i) Nucleus is positively charged.
ii) Nucleus contains electrons.
iii) Electrons revolve around the nucleus.
iv) Most of the space inside the atom is empty.
A) (ii) only
B) (i), (iii) and (iv)
C) (iv) only
D) (i) and (iv)
Answer:
D) (i) and (iv)

Question 104.

In the above table ‘x’ can be replaced by
A) 28
B) 30
C) 18
D) 8
Answer:
C) 18

Question 105.
The standard notation of an atom is \({ }_{\mathbf{Z}}^{\mathrm{A}} \mathbf{X}\). The option which shows oxygen atom is
A) \({ }_{8}^{16} \mathrm{O}\)
B) \({ }_{16}^{6} \mathrm{O}\)
C) \({ }_{16}^{8} \mathrm{O}\)
D) \({ }_{6}^{16} \mathrm{O}\)
Answer:
\({ }_{8}^{16} \mathrm{O}\)

Question 106.

The distribution of electrons in the above diagram represents the element
A) Neon
B) Nitrogen
C) Carbon
D) Oxygen
Answer:
C) Carbon

Question 107.
In the diagram regarding question number (9) the symbol ‘+’ represent
A) Protons
B) Neutrons
C) Protons and Neutrons
D) Electrons
Answer:
A) Protons

Question 108.
The sum of no. of protons and no. of neutrons is called mass number. The no. of neutrons present in the sodium atom whose atomic number is
A) 11
B) 12
C) 34
D) 23
Answer:
B) 12

Question 109.
In atoms electrons are distributed in different shells. The correct order of distribution of 12 electrons in Magnesium is
A) 2, 8, 2
B) 2, 2, 2, 6
C) 2, 2, 8
D) 2, 2, 6, 2
Answer:
A) 2, 8, 2

Question 110.
Which metal was used in Rutherford alpha scattering experiment ?
A) Silver
B) Aluminium
C) Gold
D) Platinum
Answer:
C) Gold

Question 111.
The maximum electrons present in Mshell
A) 2
B) 8
C) 18
D) 32
Answer:
C) 18

Question 112.
\({ }_{6}^{12} \mathrm{C} \quad{ }_{6}^{13} \mathrm{C} \quad{ }_{6}^{14} \mathrm{C}\)
Observe the carbon isotopes given above and answer the question. What are the neutron numbers of the above isotopes respectively ?
A) 6, 7, 8
B) 6, 6, 6
C) 18, 19, 20
D) 8, 6, 7
Answer:
A) 6, 7, 8

Question 113.
There are 3 isotopes of carbon. Carbon-12, Carbon-13 and Carbon-14. The most abundant carbon isotope is carbon – 12.
What is the average atomic mass of carbon ?
A) 12.01
B) 14.0
C) 16.0
D) 35.5
Answer:
A) 12.01

Question 114.
The property of having 8 electrons in the outer most orbit is called
A) Atomicity
B) Valency
C) Octet
D) Inertness
Answer:
C) Octet

Question 115.
The number of outermost electrons present in Na⁺ ion is
A) 8
B) 11
C)10
D) 2
Answer:
A) 8

Question 116.
If we use iodised salt in our daily we can be prevented by the disease
A) Cancer
B) Goitre
C) Skin disease-Eezima
D) Ulcer
Answer:
B) Goitre

Question 117.
Goitre – Isotope of iodine :: Cancer : ………………….
A) Isotope of Uranium
B) Isotope of Carbon
C) Isotope of Cobalt
D) Isotope of Chlorine
Answer:
C) Isotope of Cobalt

Question 118.
In Rutherford’s gold foil experiment, the emitted particles/rays
A) Beta particle
B) Gamma particle
C) X-ray particle
D) Alpha particle
Answer:
D) Alpha particle

Question 119.
The arrangement of electrons in Oxygen is
A) 2, 2, 2
B) 2, 2, 4
C) 2, 2, 6
D) 2, 4, 2
Answer:
B) 2, 2, 4

Question 120.
According to which rule, there should be two electrons in the innermost shell
A) Bohr
B) Thomson
C) Bohr-Bury
D) Rutherford
Answer:
C) Bohr-Bury

Question 121.
Match the following.

A) P – U, Q – S, R -T
B) P – T, Q – S, R – U
C) P – S, Q -T, R – U
D) P – S, Q – U, R – T
Answer:
D)P – S, Q – U, R – T

Practice the AP 9th Class Physical Science Bits with Answers Chapter 3 Is Matter Pure? on a regular basis so that you can attempt exams with utmost confidence.

AP State Syllabus 9th Class Physical Science Bits 3rd Lesson Is Matter Pure? with Answers

Question 1.
Pure substance among the following is
A) sodium chloride
B) copper sulphate
C) gold
D) air
Answer:
C) gold

Question 2.
The components of a solution are
A) solute
B) solvent
C) both A & B
D) no components
Answer:
C) both A & B

Question 3.
If the amount of solute is less than the saturation level of a solution, then the solution is said to be
A) saturated solution
B) unsaturated solution
C) super saturated solution
D) heterogeneous solution
Answer:
B) unsaturated solution

Question 4.
Factors effecting the solubility are
A) temperature of the solvent
B) size of the particles of the solute
C) stirring of contents
D) all the above
Answer:
D) all the above

Question 5.
The measurement of amount of solute that dissolves in a solvent is
A) solubility
B) diluted
C) concentrated
D) saturated
Answer:
A) solubility

Question 6.
Which of the following is an emulsion?
A) salt solution
B) mixture of oil and water
C) nail polish
D) cheese
Answer:
B) mixture of oil and water

Question 7.
Which of the following is a suspension?
A) salt solution
B) mixture of oil and water
C) nail polish
D) cheese
Answer:
C) nail polish

Question 8.
Which of the following is a colloidal dispersion ?
A) salt solution
B) mixture of oil and water
C) nail polish
D) cheese
Answer:
D) cheese

Question 9.
Which of the following is miscible liquid ?
A) sand in water
B) alcohol in water
C) oil in water
D) none
Answer:
B) alcohol in water

Question 10.
Immiscible liquids can he separated by
A) separating funnel
B) centrifuge
C) fractional distillation column
D) filtration
Answer:
A) separating funnel

Question 11.
Example of compound is
A) mercury
B) copper sulphate
C) aluminium
D) boron
Answer:
B) copper sulphate

Question 12.
Something with no adulteration means …………………. substance.
A) pure
B) impulse
C) specific
D) normal
Answer:
A) pure

Question 13.
When mixture of liquids are spun rapidly …………………. component stay at the top. This is the principle of …………………..
A) heavier, churning
B) lighter, churning
C) heavier, mixing
D) lighter, mixing
Answer:
B) lighter, churning

Question 14.
When the components of the mixture formed are uniformly distributed through out it there it is called ………………….. mixture.
A) homogeneous
B) heterogeneous
C) aqueous
D) settle
Answer:
A) homogeneous

Question 15.
When the components of the mixture formed are not distributed uniformly throughout it, then the mixture is called ……………………. mixture.
A) homogeneous
B) heterogeneous
C) aqueous
D) none
Answer:
B) heterogeneous

Question 16.
In a solution, the substance which dissolves another is called ……………………..
A) solution
B) solute
C) solvent
D) solubility
Answer:
C) solvent

Question 17.
In a solution, the substance which dissolved in another is called …………………
A) solution
B) solute
C) solvent
D) solubility
Answer:
B) solute

Question 18.
Example for solid solution is ………………….
A) alloy
B) aerated drinks
C) amalgum
D) salt solution
Answer:
A) alloy

Question 19.
The amount of solute present in a saturated solution at a certain temperature is called …………………..
A) dissolution
B) solubility
C) concentration
D) none of these
Answer:
B) solubility

Question 20.
If the amount of solute is little in a solution, then it is said to be ………………….. solution.
A) diluted
B) concentrated
C) aqueous
D) none of these
Answer:
A) diluted

Question 21.
If the amount of solute is more in a solution, then it is said to be ……………….. solution.
A) diluted
B) concentrated
C) aqueous
D) none of these
Answer:
B) concentrated

Question 22.
The amount of solute present in a given amount of solution is called …………………….. of the solution.
A) diluted
B) solubility
C) concentration
D) none of these
Answer:
C) concentration

Question 23.
Mass by mass percentage of a solution =
A) \(\frac{\text { mass of solute }}{\text { mass of solution }}\) × 100
B) \(\frac{\text { mass of solute }}{\text { mass of solvent }}\) × 100
C) \(\frac{\text { mass of solution }}{\text { mass of solute }}\) × 100
D) \(\frac{\text { mass of solvent }}{\text { mass of solute }}\) × 100
Answer:
A) \(\frac{\text { mass of solute }}{\text { mass of solution }}\) × 100

Question 24.
A mixture consisting of two liquids that do not mix and settle into layers when they left undisturbed is called …………………….
A) solution
B) suspension
C) emulsion
D) none of these
Answer:
C) emulsion

Question 25.
A heterogeneous mixture in which the solute particles do not dissolve and are visible to naked eye is called ………………………..
A) solution
B) suspension
C) emulsion
D) colloidal
Answer:
B) suspension

Question 26.
Coloured pigments in plants can be separated by ………………………..
A) distillation
B) evaporation
C) fractional distillation
D) paper chromatography
Answer:
D) paper chromatography

Question 27.
A liquid is said to be ……………….. if it dissolves completely.
A) miscible
B) immiscible
C) both A & B
D) none of these
Answer:
A) miscible

Question 28.
A liquid is said to be ………………….. if it does not dissolve but form a layer over another liquid.
A) miscible
B) immiscible
C) both A & B
D) neither A nor B
Answer:
B) immiscible

Question 29.
If the difference in boiling points of two miscible liquids is greater than 25°C, then they are separated by ……………………..
A) distillation
B) fractional distillation
C) separating funnel
D) evaporation
Answer:
A) distillation

Question 30.
Statement – I : Air is homogeneous mixture of many gases.
Statement – II: They are separated by fractional distillation.
A) Both the statements are true.
B) Statement -1 is true and statement – II is false.
C) Statement -1 is false and statement – II is true.
D) Both the statements are false.
Answer:
A) Both the statements are true.

Question 31.
Substances which can be separated into two or more components by chemical reactions are called as ……………………….
A) elements
B) mixtures
C) compounds
D) none of these
Answer:
C) compounds

Question 32.
The basic form of matter that cannot be broken down into simpler substances in chemical reactions is ……………………
A) element
B) compound
C) mixture
D) none of these
Answer:
B) compound

Question 33.
The first definition of an element is given by …………………..
A) Robert Boyle
B) Hennig Brand
C) Lavoisier
D) Burzelius
Answer:
C) Lavoisier

Question 34.
Some liquids have the property of mixing in all proportions, forming a homogeneous solution. This property is known as …………………….
A) miscibility
B) solubility
C) immiscibility
D) none of these
Answer:
A) miscibility

Question 35.
………………….. is the main factor in separating two immiscible liquids.
A) Pressure
B) Volume
C) Density
D) Mass
Answer:
C) Density

Question 36.
………………… are heterogeneous mixtures in which the particle size is too small to be seen with the naked eye but is big enough to scatter fight.
A) Suspension
B) Solutions
C) Colloids
D) None of these
Answer:
C) Colloids

Question 37.
Air is a …………………..
A) mixture
B) colloid
C) solution
D) none of these
Answer:
C) solution

Question 38.
Nail polish is a …………………..
A) solution
B) colloid
C) suspension
D) none of these
Answer:
C) suspension

Question 39.
Sodium is an …………………..
A) element
B) compound
C) suspension
D) emulsion
Answer:
A) element

Question 40.
Methane is an ……………………..
A) element
B) compound
C) suspension
D) emulsion
Answer:
B) compound

Question 41.
Steel is a ………………….
A) solid solution
B) liquid solution
C) gaseous solution
D) salt solution
Answer:
A) solid solution

Question 42.
Cold cream is ……………………….
A) solution
B) suspension
C) colloid
D) emulsion
Answer:
D) emulsion

Question 43.
Assertion (A) : Air is compound substance.
Reason (R) : We can separate air into two or more components only by means of a chemical reaction.
A) A and R are true
B) A and R are false
C) A is true but R is false
D) A is false but R is true
Answer:
B) A and R are false

Question 44.
All the solutions are ‘x’s. But not all ‘x’s are solutions. Guess the ‘x’.
A) Pure substance
B) Mixture
C) Atom
D) Liquid
Answer:
B) Mixture

Question 45.
If a solution is diluted, the path of the fight beam is
A) Visible
B) Not visible
C) Lightly visible
D) Sometimes visible
Answer:
B) Not visible

Question 46.
‘A’ is a mixture. No particles are settled down when it left undisturbed for sometime. Light beam is visible through it. Guess the ‘A’.
A) Solution
B) Colloid
C) Suspension
D) A or B
Answer:
B) Colloid

Question 47.
Take concentrated solution of copper sulphate in a beaker. Drop a piece of aluminium foil in it. Then,
A) Copper deposites on the aluminium foil
B) Aluminium dissolves
C) The solution becomes colourless
D) A and C
Answer:
D) A and C

Question 48.
Copper cannot be separated from copper sulphate by physical methods. So, it is
A) mixture
B) compound
C) A or B
D) colloid
Answer:
B) compound

Question 49.
The mixture of water and sugar is
A) suspension
B) colloid
C) homogeneous mixture
D) heterogeneous mixture
Answer:
C) homogeneous mixture

Question 50.
In a solution of tincture iodine, alcohol is
A) solution
B) solvent
C) solute
D) does not exist
Answer:
B) solvent

Question 51.
The technique used to separate the mixture of camphor and water is
A) distillation
B) fractional distillation
C) sublimation
D) handpicking
Answer:
C) sublimation

Question 52.
Miscible liquids, when the difference between their boiling points is < 25°C can be separated by
A) separating funnel
B) distillation
C) fractional distillation
D) evaporation
Answer:
C) fractional distillation

Question 53.
The scattering of beam of light when light passes through a colloidal solution is ………………………….
A) Raman effect
B) Crompton effect
C) Photo electric effect
D) Tyndall effect
Answer:
D) Tyndall effect

Question 54.
Dye present in an ink can be separated by ………………..
A) distillation
B) evaporation
C) fractional distillation
D) paper chromatography
Answer:
B) evaporation

Question 55.
Urine is boiled down to discover phosphorous by ……………………
A) Robert Boyle
B) Hennig Brand
C) Lavoisier
D) Burzelius
Answer:
B) Hennig Brand

Question 56.
Acetone and water are separated by ………………..
A) Distillation
B) Chromatography
C) Sublimation
D) Fractional distillation
Answer:
A) Distillation

Question 57.
Kerosene and water are separated by ………………….
A) Distillation
B) Separating funnel
C) Sublimation
D) Fractional distillation
Answer:
B) Separating funnel

Question 58.
Assertion (A) : Water + sugar is a solution.
Reason (R) : If we pass beam of light through a solution, it scatters light.
A) A and R are true
B) A and R are false
C) A is true but R is false
D) A is false but R is true
Answer:
C) A is true but R is false

Question 59.
Take two test tubes with some water. Add salt powder to one test tube and add crystals of salt to the second one. Observe. From your observation you may conclude that solubility depends upon
A) temperature
B) size of the solute
C) stirring
D) above all
Answer:
B) size of the solute

Question 60.
The correct process is
a) add solvent more to dilute a solution
b) add solute more to dilute a solution
c) add solute more to concentrate a solution
d) add solvent more to concentrate a solution
A) b, d
B) a, c
C) b, c
D) a, d
Answer:
D) a, d

Question 61.
Which of the given device is used to separate a mixture of kerosene and water ?
A) conical flask
B) burette
C) pipette
D) test tube
Answer:
B) burette

Question 62.
Tindal effect observes in the following substances by passing light through it
A) salt solution
B) milk
C) copper sulphate solution
D) starch solution
A) B only
B) A, D
C) C only
D) B, D
Answer:
A) B only

Question 63.
Which apparatus is required to check whether milk is colloid or true solution ?
A) filter paper
B) laser light
C) burner
D) A and B
Answer:
B) laser light

Question 64.
How do you examine whether a starch solution is colloid or suspension ?
A) By sending light beam
B) By leaving undisturbed for some-time
C) By heating it
D) Any of the above
Answer:
B) By leaving undisturbed for some-time

Question 65.
How do you separate a miscible liquid in your lab ?
A) By using separating funnel
B) By using distillation method
C) By using evaporation method
D) By using sublimation method
Answer:
B) By using distillation method

Question 66.
Cream from milk can be separated by
A) centrifugation
B) distillation
C) fractional distillation
D) chromatography
Answer:
A) centrifugation

Question 67.
Tyndall effect cannot be shown by
A) colloids
B) suspensions
C) emulsions
D) solutions
Answer:
D) solutions

Question 68.
The component of the air among the following which has the highest boiling point is
A) nitrogen
B) argon
C) methane
D) oxygen
Answer:
C) methane

Question 69.
The first definition for ‘element’ is given by
A) Lavoisier
B) Hennig Brand
C) Sir Humphry Davy
D) Robert Boyle
Answer:
A) Lavoisier

Question 70.
Coloured gem stone is an example of …………………
A) solution
B) suspension
C) colloid
D) emulsion
Answer:
C) colloid

Question 71.
Ink is mixture of …………………. in water.
A) dye
B) salt
C) sugar
D) acid
Answer:
A) dye

Question 72.
The term element is first used by ……………………
A) Robert Boyle
B) Hennig Brand
C) Lavoisier
D) Burzelius
Answer:
A) Robert Boyle

Question 73.
Percentage of oxygen in air by volume ………………………
A) 20.9%
B) 78.1%
C) 0.03%
D) 0.1%
Answer:
A) 20.9%

Question 74.
Percentage of nitrogen in air by volume ………………………
A) 20.9%
B) 78.1%
C) 0.03%
D) 0.1%
Answer:
B) 78.1%

Question 75.
Percentage of argon in air by volume
A) 20.9%
B) 78.1%
C) 0.03%
D) 0.9%
Answer:
D) 0.9%

Question 76.
Components of blood sample are separated by ………………..
A) Distillation
B) Sublimation
C) Fractional distillation
D) Centrifugation
Answer:
D) Centrifugation

Question 77.
Naphthalene in water separated by ………………….
A) distillation
B) chromatography
C) sublimation
D) centrifugation
Answer:
C) sublimation

Question 78.
Petrochemicals are separated by …………………..
A) fractional distillation
B) distillation
C) sublimation
D) separating funnel
Answer:
A) fractional distillation

Question 79.
A) kerosene + salt
B) water + salt
C) water + sugar
D) salt + sugar
In the above mixtures, heterogeneous is /are
A) B, C
B) A, B, C
C) A
D) A, D
Answer:
D) A, D

Question 80.
a) sugar water
b) tincture of iodine
c) soda water
d) salt water
The above given mixtures are
A) Homogeneous mixtures
B) Heterogeneous mixtures
C) Solutions
D) A and C
Answer:
D) A and C

Question 81.

X and Y are
A) suspension and solution
B) suspension and colloid
C) solution and suspension
D) colloid and suspension
Answer:
A) suspension and solution

Question 82.
Milk, butter, cheese, cream, gel, boot polish
These are
A) suspensions
B) colloids
C) solutions
D) B & C
Answer:
B) colloids

Question 83.

Substance ‘C’ is
A) Milk
B) Salt water
C) Air
D) Butter milk
Answer:
D) Butter milk

Question 84.
(a) set A : fog, clouds, mist
(b) set B : foam, rubber, sponge
(c) set C : jelly, cheese, butter
Which of the above is contained solid as dispersion media ?
A) b
B) c
C) a
D) b and c
Answer:
D) b and c

Question 85.

Which of the above are pure substances ?
A) a, d
B) d, e
C) e
D) a, b, c
Answer:
C) e

Question 86.
What would you notice from the given figure ?

A) Pure substances
B) Mixtured substances
C) Both A and B
D) None
Answer:
A) Pure substances

Question 87.
What would you notice from the given figure?

A) Pure substances
B) Mixtured substances
C) Both A and B
D) None
Answer:
B) Mixtured substances

Question 88.
Name the set up given in the figure.

A) Separation funnel
B) Fractional distillation
C) Separation of components in air
D) None
Answer:
B) Fractional distillation

Question 89.
Name the set up given in the figure.

A) Separation funnel
B) Fractional distillation
C) Separation of components in air
D) None
Answer:
A) Separation funnel

Question 90.
Name the set up given in the figure.

A) Separation funnel
B) Fractional distillation
C) Separation of components in air
D) None
Answer:
C) Separation of components in air

Question 91.

The given figure is related to
A) sublimation
B) fractional distillation
C) paper chromatography
D) evaporation
Answer:
C) paper chromatography

Question 92.

This is a diagram of a separating fun-nel. The parts 1 and 2 are ………………., …………… respectively.
A) low density liquid, high density liquid
B) low density gas, high density liquid
C) high density liquid, low density liquid
D) high density gas, low density liquid
Answer:
A) low density liquid, high density liquid

Question 93.
‘Churning makes the lighter components to come to the surface when a mixture of liquids are spun rapidly’. This principle is used in
A) Refrigerators
B) Centrifuge
C) Microscope
D) Rice cookers
Answer:
B) Centrifuge

Question 94.
Generally solid solutions are available in
A) alloys
B) gems
C) glasses
D) above all
Answer:
D) above all

Question 95.
80 ml of solution contains 20 gr of solute. The mass by volume percentage of the solution is
A) 20%
B) 40%
C) 25%
D) 80%
Answer:
C) 25%

Question 96.
Anitha observed, ‘Shake well before use’ on a label of cough syrup bottle. ‘ The syrup is
A) solution
B) colloid
C) suspension
D) above all
Answer:
C) suspension

Question 97.
Ravi observed a beam of sun light passing through a small hole on the roof, into the room. It is formed because
A) air is colloid
B) air is true solution
C) air is suspension
D) air is pure substance
Answer:
A) air is colloid

Question 98.
Tyndall effect is observed by
A) colloids
B) solutions
C) suspensions
D) pure substances
Answer:
A) colloids

Question 99.
Which of the given mixtures cannot be separated by simple physical method ?
A) Husk in grains
B) Stones in rice
C) Fat in milk
D) Oxygen from water
Answer:
D) Oxygen from water

Question 100.
Which method is suitable to separate salt from sea water ?
A) sublimation
B) evaporation
C) chromatography
D) distillation
Answer:
B) evaporation

Question 101.
Petroleum is separated into its components by
A) distillation
B) fractional distillation
C) evaporation
D) filtration
Answer:
B) fractional distillation

Question 102.
Sir, Humphry Davy is appreciable, because, he was extremely successfuil in
A) discovering many elements like Na, Mg, B, Cl, etc.
B) giving useful definition of element.
C) separating of components of air.
D) above all
Answer:
A) discovering many elements like Na, Mg, B, Cl, etc.

Question 103.
The mass by mass percentage concentration of a 100g salt solution, which contains 20g salt is
A) 10%
B) 20%
C) 30%
D) 50%
Answer:
B) 20%

Question 104.
The separation technique to separate sodium chloride from its solution in water is
A) sublimation
B) condensation
C) evaporation
D) filtration
Answer:
C) evaporation

Question 105.
By which method do you separate Ammonium chloride from a mixture containing Sodium chloride and Ammonium chloride ?
A) sublimation
B) condensation
C) evaporation
D) filtration
Answer:
A) sublimation

Question 106.
How do you separate small pieces of metal in the engine oil of a car ?
A) sublimation
B) condensation
C) evaporation
D) filtration
Answer:
D) filtration

Question 107.
How do you separate different pigments from an extract of flower petals ?
A) sublimation
B) chromatography
C) evaporation
D) distillation
Answer:
B) chromatography

Question 108.
In your home, how do you separate butter from curd ?
A) evaporation
B) chromatography
C) churning
D) distillation
Answer:
C) churning

Question 109.
Match the following.

A) a – 3, b – 2, c -1
B) a – 2, b -1, c – 3
C) a -1, b – 2, c – 3
D) a – 3, b -1, c – 2
Answer:
D) a – 3, b -1, c – 2

Question 110.
This is not a property of colloid.
A) scattering light
B) tyndall effect
C) sedimentation
D) A and C
Answer:
C) sedimentation

Question 111.
Some colloids in your home are
A) gel
B) milk
C) oil
D) boot polish
A) A, B
B) B, C
C) A, B, D
D) A, B, C
Answer:
A) A, B

Question 112.
Some pure substances in your home are
a) ice
b) milk
c) iron
d)air
e) water
f) gold
g) coal
A) a, b, c, d
B) c, b, d, g
C) d, e, f, g
D) a, c, e, f, g
Answer:
D) a, c, e, f, g

Question 113.
Ice cream is a
A) suspension
B) colloid
C) emulsion
D) solution
Answer:
B) colloid

Question 114.
The ingredients in ice cream are………………
A) milk
B) sugar
C) flavours
D) all of these
Answer:
D) all of these

Question 115.
Shaving cream is a …………….. type of colloid.
A) foam
B) emulsion
C) aerosol
D) solution
Answer:
A) foam

Question 116.
In automobile exhaust, the dispersion medium is ………………..
A) solid
B) liquid
C) gas
D) solution
Answer:
C) gas

Question 117.
Clouds are ………………..
A) solution
B) suspension
C) colloid
D) emulsion
Answer:
C) colloid

Question 118.
Colloidal solutions are heterogeneous in nature and always consist of altleast two phases, the disperse phase and the dispersion medium. Which of the following is not a colloidal solution ?
A) Shoe polish
B) Mud water
C) Gel
D) Ice cream
Answer:
B) Mud water

Question 119.
Acetone – Water : Distillation : : Ammonium chloride – Salt:
A) Sedimentation
B) Filtration
C) Sublimation
D) Fractional distillation
Answer:
C) Sublimation

Question 120.
The correct order of sentences related to preparation of super saturated solution is
P. Add one more spoon of sugar to it
Q. Add one spoon of sugar to 100 ml of water in a breaker
R. On heating the undissolved sugar dissolves to form a super saturated solution
S. It dissolves totally to form saturated solution
A) Q, S, P, R
B) Q, R, P, S
C) P, Q, R, S
D) Q, P, R, S
Answer:
A) Q, S, P, R

Question 121.
On mixing of dil. hydrochloric acid to the mixture of iron dust and sulphur powder we obtain two gases. One of them is hydrogen and another would be
A) Sulphur dioxide
B) Hydrogen sulphide
C) Sulphur trioxide
D) Oxygen
Answer:
A) Sulphur dioxide

Question 122.
Assertion (A) : We feel cool after sweating.
Reason (R) : We store water in earthen pots during summer.
A) Both (A), (R) are correct, (R) is not the correct explanation of (A).
B) (A) is correct, (R) is incorrect.
C) (A) is incorrect, (R) is correct.
D) Both (A), (R) are correct, (R) is the correct explanation of (A).
Answer:
A) Both (A), (R) are correct, (R) is not the correct explanation of (A).

Question 123.
Assertion (A) : Chromatography is used to separate the coloured pigments in flowers.
Reason (R) : Chromatography is a technique for the separation of mixtures into its individual components.
A) Both assertion (A) and reason (R) are correct and (R) is the correct explanation of (A).
B) Assertion (A) is correct but reason (R) is incorrect.
C) Assertion (A) is incorrect but reason (R) is correct.
D) Both assertion (A) and reason (R) are correct but (R) is not correct explanation of (A).
Answer:
A) Both assertion (A) and reason (R) are correct and (R) is the correct explanation of (A).

Question 124.
Ink is a mixture of a dye in water. We can separate the components in the ink using evaporation. The correct observation in the experiment is
i) Water is separated in the form of vapour.
ii) Dye component doesn’t evaporate.
iii) Water and dye components gets evaporated.
iv) Dye components gets sublimated.
A) (i) and (ii)
B) (iii) only
C) (i) and (iv)
D) (i) only
Answer:
A) (i) and (ii)

Question 125.
On adding a piece of aluminium foil to blue coloured copper sulphate solution, copper will be deposited on aluminium foil. Then the solution
A) No change in colour
B) Becomes colourless
C) Turns to red
D) Turns to green
Answer:
B) Becomes colourless

Question 126.

In the above table ‘x’ can be replaced
A) Liquid
B) Solid
C) Solid or liquid
D) Gas
Answer:
C) Solid or liquid

Question 127.
Element is a basic form of matter that cannot be broken down into simple forms by chemical reactions. If any substance can be separated into two or more constituent parts by a chemical reaction it should be
A) Mixture
B) Heterogeneous mixture
C) Homogeneous mixture
D) Compound
Answer:
D) Compound

Question 128.
Diesel – water is an immiscible mixture of solution. The diagram of apparatus is used to separate the mixture is

Answer:

Question 129.
The amount in gr mass of solute present in 100 gr mass of solution is called concentration. If 50 gr of salt in 200 gr of water, the concentration, of that solution would be
A) 25%
B) 10%
C) 50%
D) 20%
Answer:
D) 20%

Question 130.
In hot summer Revathi gave lemonade to the guests who visited her home. The solute in that solution is/are
i) Water
ii) Lemon juice
iii) Sugar
iv) Salt
A) (i) and (ii)
B) (iii) and (iv)
C) (ii), (iii) and (iv)
D) (i) only
Answer:
C) (ii), (iii) and (iv)

Question 131.
The components of a homogenous mixture are too intimately mixed up that it will be difficult to distinguish them from each other by visual observation. Example for such mixture is
A) Kerosene-water
B) Air
C) Naphthalein-water
D) Oil-water
Answer:
B) Air

Question 132.
Solubility is the measurement of amount of solute that dissolves in a solvent at a certain temperature. Factors that affect the solubility are
i) Temperature
ii) Size of the solute particles
iii) Stirring of a solution
A) (i) and (ii)
B) (ii) and (iii)
C) (i), (ii) and (iii)
D) (i) Only
Answer:
C) (i), (ii) and (iii)

Question 133.
Milk is
A) Suspension
B) Emulsion
C) Colloid
D) Gel
Answer:
C) Colloid

Question 134.
When we go through deep forest, the following effect can be observed
A) Photo electric effect
B) Raman effect
C) Tyndall effect
D) Comphton effect
Answer:
C) Tyndall effect

Question 135.
There must be following apparatus in chromotography laboratory activity
A) Thermometer
B) Litmus paper
C) Marker pen
D) Kerosene
Answer:
C) Marker pen

Question 136.
Which of the following is NOT a property of a mixture ?
A) They can formed from elements or compounds.
B) They have the properties of the constituent substances.
C) Their composition is always fixed.
D) They can be separated by physical methods.
Answer:
C) Their composition is always fixed.

Question 137.
A teaspoon of salt is mixed with a teaspoon of powdered camphor. Which of the following methods can be used to separate the camphor from this mixture ?
A) Distillation
B) Evaporation
C) Chromatography
D) Sublimation
Answer:
D) Sublimation

Question 138.
Which of the following is NOT a pure substance ?
A) Gold
B) Glucose
C) Milk
D) Water
Answer:
C) Milk

Question 139.
Take two test tubes, one filled with water and one with kerosene. Now add a spoon of salt in both and stir. You will observe that in the first test tube the salt dissolves completely and in the second test tube it does not dissolve. Which of the following is being tested using the above experiment ?
A) To identify which substance is pure substance and which is a mixture.
B) To identify which mixture is homogeneous and which is heterogeneous.
C) To identify if water and kerosene are a solute or a solvent.
D) To identify which is a saturated solution and which is an unsaturated solution.
Answer:
B) To identify which mixture is homogeneous and which is heterogeneous.

Question 140.
If the amount of the solute present is little for a given volume of solution, the solution is said to be dilute. If the amount of the solute present is more for a given volume of solution, the solution is said to be concentrated. Concentration is the mass of solute dissolved in the given volume of the solution.

Solution X contains 50 g of salt in 100g of water and solution Y contains 100g of salt in 200g of water.
Which of the following can be true based on the above information ?
A) Solution X has the same concentration as solution Y.
B) Solution X is more concentrated than solution Y.
C) Solution X is more dilute than solution Y.
D) Concentration of X cannot be compared with that of solution Y as their volumes are different.
Answer:
A) Solution X has the same concentration as solution Y.

Question 141.

Choose the correct matching.
A) i – r, ii – s, iii – q, iv – p
B) i – s, ii – q, iii – p, iv – r
C) i – q, ii – p, iii – r, iv – s
D) i – p, ii – r, iii – s, iv – q
Answer:
A) i – r, ii – s, iii – q, iv – p

Question 142.
Which of the following cannot be separated by sublimation when it is mixed with Sand
A) Salt
B) Ammonium Chloride
C) Camphor
D) Iodine
Answer:
A) Salt

Question 143.
Ram : Salt is a compound.
Raj : Salt is a mixture. Who is correct ?
A) Ram
B) Raj
C) Both
D) None
Answer:
A) Ram

Question 144.
Kerosene and Caster oil are immisible liquids. To separate kerosene from caster oil ……………… is used typetype
A) Filter paper
B) Funnel
C) Separating funnel
D) Distillation apparatus
Answer:
D) Distillation apparatus