Here are MCQs with answers for Class 11 Chemistry, Chapter 5 – States of Matter. These questions are designed according to the latest CBSE curriculum and Class 11 syllabus. Practicing these MCQs will help students quickly revise the key concepts from the chapter and get ready for the Class 11 Annual exams, as well as other competitive exams like NEET and JEE.
Class 11 States of Matter MCQs Question with Answers
1. What is the SI unit of pressure?
a) Atmosphere
b) Pascal
c) Bar
d) Torr
Answer: b) Pascal
2. The relationship between pressure and volume of a gas is given by which law?
a) Boyle’s Law
b) Charles’s Law
c) Avogadro’s Law
d) Dalton’s Law
Answer: a) Boyle’s Law
3. Which of the following is not a property of gases?
a) Gases have fixed volume.
b) Gases have indefinite shape.
c) Gases are highly compressible.
d) Gases exert pressure.
Answer: a) Gases have fixed volume.
4. Which of these is the most ideal gas at low pressure and high temperature?
a) H₂
b) He
c) N₂
d) CO₂
Answer: b) He
5. The van der Waals equation corrects which ideal gas assumption?
a) Gas molecules do not interact with each other.
b) The volume of gas molecules is negligible.
c) Gas molecules are perfectly spherical.
d) Gas molecules have high kinetic energy.
Answer: a) Gas molecules do not interact with each other.
6. What does Avogadro’s law state?
a) Volume is directly proportional to pressure.
b) Volume is directly proportional to temperature.
c) Volume is directly proportional to the number of moles.
d) Volume is inversely proportional to temperature.
Answer: c) Volume is directly proportional to the number of moles.
7. The critical temperature of a gas is:
a) The temperature above which a gas cannot be liquefied.
b) The temperature at which a gas is liquefied.
c) The temperature at which gas molecules become stable.
d) The temperature where pressure becomes zero.
Answer: a) The temperature above which a gas cannot be liquefied.
8. Which of the following is an example of a real gas?
a) Nitrogen
b) Oxygen
c) Carbon dioxide
d) Hydrogen
Answer: c) Carbon dioxide
9. In which of the following states of matter do particles have the highest energy?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: d) Plasma
10. Which of the following factors affects the rate of diffusion of gases?
a) Volume
b) Temperature
c) Pressure
d) Mass of molecules
Answer: b) Temperature
11. The term ‘critical point’ refers to the condition at which:
a) Gas cannot be compressed anymore.
b) Liquid and gas become indistinguishable.
c) A gas liquefies easily.
d) The temperature becomes zero.
Answer: b) Liquid and gas become indistinguishable.
12. The shape and volume of a liquid are:
a) Fixed
b) Fixed volume, variable shape
c) Fixed shape, variable volume
d) Variable shape, variable volume
Answer: b) Fixed volume, variable shape
13. Which of the following gases is the least ideal?
a) H₂
b) N₂
c) CO₂
d) He
Answer: c) CO₂
14. Boyle’s Law is applicable at:
a) Low temperature and high pressure
b) Low pressure and high temperature
c) High pressure and high temperature
d) High pressure and low temperature
Answer: b) Low pressure and high temperature
15. Which law describes the relationship between the volume of a gas and its temperature at constant pressure?
a) Avogadro’s Law
b) Charles’s Law
c) Gay-Lussac’s Law
d) Boyle’s Law
Answer: b) Charles’s Law
16. If the temperature of a gas is doubled, what will happen to its volume (at constant pressure)?
a) It will be halved.
b) It will be doubled.
c) It will remain the same.
d) It will increase four times.
Answer: b) It will be doubled.
17. A gas behaves most ideally under:
a) High pressure and low temperature
b) Low pressure and high temperature
c) Low temperature and high temperature
d) High pressure and low temperature
Answer: b) Low pressure and high temperature
18. The ideal gas equation is:
a) PV = nRT
b) P = V/T
c) P = nV/T
d) V = nRT/P
Answer: a) PV = nRT
19. Which of the following statements is true for solids?
a) They have indefinite shape but fixed volume.
b) They have fixed shape and fixed volume.
c) They have indefinite shape and indefinite volume.
d) They have fixed shape but variable volume.
Answer: b) They have fixed shape and fixed volume.
20. The gas law that is a combination of Boyle’s and Charles’s Law is:
a) Avogadro’s Law
b) Gay-Lussac’s Law
c) Ideal Gas Law
d) Dalton’s Law
Answer: c) Ideal Gas Law
21. Which of the following is a characteristic of a gas?
a) It has a definite shape.
b) It has a definite volume.
c) It is highly compressible.
d) Its particles are arranged in a fixed pattern.
Answer: c) It is highly compressible.
22. The compressibility factor for an ideal gas is:
a) 0
b) 1
c) Infinite
d) 0.5
Answer: b) 1
23. The temperature at which the kinetic energy of molecules becomes zero is:
a) -273.15°C
b) 0°C
c) 100°C
d) 273.15°C
Answer: a) -273.15°C
24. The boiling point of a liquid increases with:
a) Increase in atmospheric pressure
b) Decrease in atmospheric pressure
c) Increase in temperature
d) Decrease in temperature
Answer: a) Increase in atmospheric pressure
25. The volume of a gas is directly proportional to:
a) Its mass
b) Its temperature
c) Its pressure
d) Its volume
Answer: b) Its temperature
26. The intermolecular forces in gases are:
a) Very strong
b) Moderate
c) Weak
d) None
Answer: c) Weak
27. The pressure exerted by a gas is directly proportional to:
a) Volume
b) Number of particles
c) Temperature
d) Both b and c
Answer: d) Both b and c
28. In which of the following gases does the deviation from ideal behavior become significant?
a) Helium
b) Hydrogen
c) Oxygen
d) Argon
Answer: c) Oxygen
29. Which of these properties is characteristic of a solid?
a) High compressibility
b) Fixed shape
c) Flowability
d) High kinetic energy
Answer: b) Fixed shape
30. The molar volume of an ideal gas at STP is:
a) 12.22 L
b) 22.4 L
c) 32.4 L
d) 45.5 L
Answer: b) 22.4 L
31. In which of the following phases do the particles have the least energy?
a) Gas
b) Liquid
c) Solid
d) Plasma
Answer: c) Solid
32. The ideal gas law equation can be used to describe the behavior of:
a) Solids
b) Liquids
c) Gases
d) All of the above
Answer: c) Gases
33. Which of the following is an example of a real gas?
a) Helium
b) Oxygen
c) Nitrogen
d) Hydrogen
Answer: b) Oxygen
34. The movement of particles in a gas is:
a) Slow and random
b) Fast and in straight lines
c) Slow and in circular paths
d) Fast and in random directions
Answer: b) Fast and in straight lines
35. The van der Waals equation is used to describe the behavior of:
a) Ideal gases
b) Real gases
c) Solids
d) Liquids
Answer: b) Real gases
36. What happens to the volume of a gas when the pressure is doubled at constant temperature?
a) Volume is halved.
b) Volume is doubled.
c) Volume remains the same.
d) Volume increases four times.
Answer: a) Volume is halved.
37. The average kinetic energy of the molecules of a gas is directly proportional to:
a) Temperature
b) Volume
c) Pressure
d) Number of molecules
Answer: a) Temperature
38. The gas laws do not hold true for:
a) Helium
b) Hydrogen
c) Carbon dioxide
d) Oxygen
Answer: c) Carbon dioxide
39. What happens when the temperature of a gas is increased at constant pressure?
a) Volume increases
b) Volume decreases
c) Volume remains constant
d) Pressure decreases
Answer: a) Volume increases
40. A real gas will behave like an ideal gas at:
a) High temperature and high pressure
b) Low temperature and high pressure
c) Low temperature and low pressure
d) High temperature and low pressure
Answer: d) High temperature and low pressure
41. In a closed container, the pressure exerted by a gas depends on:
a) The volume of the container
b) The temperature of the gas
c) The number of molecules
d) All of the above
Answer: d) All of the above
