Class 11 Chemistry Chapter 5 States of Matter Questions and Answers

1 Which of the following changes decrease the vapour pressure of water kept in a sealed vessel?

A Decreasing the quantity of water

B Adding salt to the water

C Decreasing the volume of the vessel to one-half

D Decreasing the temperature of the water

View Answer

Answer:B, D

2 Under which of the following two conditions applied together, a gas deviates most from the ideal behaviour?

A Low pressure

B High pressure

C Low temperature

D High temperature

View Answer

Answer:B, C

3 Which of the following figures does not represent 1 mole of dioxygen gas at STP?

A 16 grams of gas

B 22.7 litres of gas

C 6.022 × 1023 dioxygen molecules

D 11.2 litres of gas

View Answer

Answer:A, D

4 With regard to the gaseous state of matter which of the following statements are correct?

A Complete order of molecules

B Complete disorder of molecules

C Random motion of molecules

D Fixed position of molecules

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Answer:B, C

5 How does the surface tension of a liquid vary with an increase in temperature?

A Remains the same

B Decreases

C Increases

D No regular pattern is followed

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Answer:Decreases

6 Increase in kinetic energy can overcome intermolecular forces of attraction. How will the viscosity of liquid be affected by the increase in temperature?

A Increase

B No effect

C Decrease

D No regular pattern will be followed

View Answer

Answer: Decrease

7 Atmospheric pressures recorded in different cities are as follows:

Cities Shimla Bangalore Delhi Mumbai

p in N/m2 1.01×105 1.2×105 1.02×105 1.21×105

Consider the above data and mark the place at which liquid will boil first.

A Shimla

B Bangalore

C Delhi

D Mumbai

View Answer

Answer:Shimla

8 What is the SI unit of viscosity coefficient (η)?

A Pascal

B Nsm–2

C km–2 s

D N m–2

View Answer

Answer:Nsm–2

9 Gases possess characteristic critical temperature which depends upon the magnitude of intermolecular forces between the particles. Following are the critical temperatures of some gases. Gases H2 He O2 N2 Critical temperature in Kelvin 33.2 5.3 154.3 126 From the above data what would be the order of liquefaction of these gases?

Start writing the order from the gas liquefying first

A H2, He, O2, N2

B He, O2, H2, N2

C N2, O2, He, H2

D O2, N2, H2, He

View Answer

Answer:O2, N2, H2, He

10 As the temperature increases, the average kinetic energy of molecules increases. What would be the effect of the increase of temperature on pressure provided the volume is constant?

A increases

B decreases

C remains the same

D becomes half

View Answer

Answer:increases

11 The pressure of a 1:4 mixture of dihydrogen and dioxygen enclosed in a vessel is one atmosphere. What would be the partial pressure of dioxygen?

A 0.8×105 atm

B 0.008 Nm–2

C 8×104Nm–2

D 0.25 atm

View Answer

Answer:8×104Nm–2

12 Dipole-dipole forces act between the molecules possessing permanent dipole. Ends of dipoles possess ‘partial charges’. The partial charge is

A more than unit electronic charge

B equal to unit electronic charge

C less than unit electronic charge

D double the unit electronic charge

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Answer:less than unit electronic charge

13 The interaction energy of the London force is inversely proportional to the sixth power of the distance between two interacting particles but their magnitude depends upon

A charge of interacting particles

B mass of interacting particles

C polarisability of interacting particles

D strength of permanent dipoles in the particles.

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Answer:polarisability of interacting particles

14 Which of the following property of water can be used to explain the spherical the shape of rain droplets?

A viscosity

B surface tension

C critical phenomena

D pressure

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Answer:surface tension

15 A person living in Shimla observed that cooking food without using pressure cooker takes more time. The reason for this observation is that at high altitude:

A pressure increases

B temperature decreases

C pressure decreases

D temperature increases

View Answer