10th class Chemistry, Chapter 14: States of Matter and Phase Changes MCQs

1. According to kinetic theory, the basic difference between solid, liquid and gas is due to:

1. (A) the difference in the movements of the particles. ✓
2. (B) the chemical properties of the particles.
3. (C) the size of the particles.
4. (D) the shape of the particles.

2. Upon heating the rate of evaporation:

1. (A) decreases
2. (B) increases ✓
3. (C) remains the same
4. (D) initially decreases and then increases upon further heating

3. The inter-particle attractions are the strongest in:

1. (A) Solids ✓
2. (B) Liquids
3. (C) Plasma
4. (D) Gas

4. Cooling the vapours of some gases change them directly into solid state. This phenomenon is called:

1. (A) evaporation
2. (B) condensation
3. (C) sublimation
4. (D) deposition ✓

5. Physical state in which the particles possess the maximum energy:

1. (A) Solid
2. (B) Liquid
3. (C) Gaseous ✓
4. (D) Vapour

6. How does the process of evaporation depend on the force of attraction present among the molecules of a liquid?

1. (A) It decreases with the increasing strength of attraction. ✓
2. (B) It increases with the increasing strength of attraction.
3. (C) It is independent of the strength of the force of attraction.
4. (D) It first increases and then decreases with the increasing strength of the force of attraction.

7. Which gas will diffuse at the fastest rate?

1. (A) HCl
2. (B) SO₂
3. (C) H₂S ✓
4. (D) CO₂

8. The phase changes A and B in gas -A→ liquid -B→ solid are:

1. (A) Melting, evaporating
2. (B) Condensation, melting
3. (C) Condensation, freezing ✓
4. (D) Boiling, freezing

9. A student noticed frost falling on the ground at 6.30 am and disappearing by 8.30 am. Which phase change was responsible for changing the frost into water vapours?

1. (A) Melting
2. (B) Evaporation
3. (C) Sublimation ✓
4. (D) Deposition

10. Matter exists in four physical states: gas, liquid, solid and:

1. (A) vapour
2. (B) plasma ✓
3. (C) crystal
4. (D) colloid

11. The pressure exerted by a gas is due to:

1. (A) attraction between its particles
2. (B) friction between its particles
3. (C) weight of its particles
4. (D) collisions of its particles with the walls of the container ✓

12. The average kinetic energy of the particles of a gas is directly proportional to the temperature measured on:

1. (A) kelvin scale ✓
2. (B) Fahrenheit scale
3. (C) any scale
4. (D) Celsius scale

13. At the same temperature, the average kinetic energy is:

1. (A) the same for all gases ✓
2. (B) zero for all gases
3. (C) greater for lighter gases
4. (D) greater for heavier gases

14. A liquid has a fixed volume because of:

1. (A) large distance between particles
2. (B) inter-particle forces ✓
3. (C) very high kinetic energy
4. (D) random motion of particles

15. The particles of a solid possess:

1. (A) all three types of motion
2. (B) vibrational motion only ✓
3. (C) translational motion only
4. (D) rotational motion only

16. Molecules present in a gas and a liquid show which types of movements simultaneously?

1. (A) rotational and vibrational only
2. (B) vibrational only
3. (C) translational, rotational and vibrational ✓
4. (D) translational only

17. Internal energy of a substance includes the kinetic energy of its particles and:

1. (A) energy of the container
2. (B) energy of the surroundings
3. (C) potential energy due to bonding between them ✓
4. (D) chemical energy of the air

18. Heat ____ the internal energy of a system.

1. (A) does not change
2. (B) increases ✓
3. (C) first decreases then increases
4. (D) decreases

19. The temperature at which a solid starts melting is called its:

1. (A) melting point ✓
2. (B) boiling point
3. (C) condensation point
4. (D) freezing point

20. Further heating a solid after it has started melting:

1. (A) makes it a gas at once
2. (B) raises its temperature rapidly
3. (C) does not increase its temperature ✓
4. (D) lowers its temperature