Chapter-12 Kinetic Theory — Online MCQ Test
PHYSICS · Grade 11 · CBSE(NCERT)
Practice Chapter-12 Kinetic Theory with a free chapter-wise online MCQ test.
This chapter covers: Equation of state - Perfect gas - Kinetic model - Gas pressure - Kinetic interpretation of temperature - RMS speed - Degrees of freedom - Law of equipartition of energy - Specific....
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter-12 Kinetic Theory — Important Questions & Answers
What is Avogadro's number?
- A. 6.02 × 10²³ mol⁻¹
- B. 6.02 × 10²² mol⁻¹
- C. 3.14 × 10²³ mol⁻¹
- D. 1.38 × 10⁻²³ mol⁻¹
Answer: A. 6.02 × 10²³ mol⁻¹
Avogadro's number is a fundamental constant equal to 6.02 × 10²³ mol⁻¹, representing the number of particles in one mole.
Avogadro's number is a fundamental constant equal to 6.02 × 10²³ mol⁻¹, representing the number of particles in one mole.
The equation of state for an ideal gas is:
- A. PV = nRT
- B. PV = RT
- C. P = nRT
- D. V = nRT/P²
Answer: A. PV = nRT
The ideal gas equation is PV = nRT, where P is pressure, V is volume, n is number of moles, R is gas constant, and T is temperature.
The ideal gas equation is PV = nRT, where P is pressure, V is volume, n is number of moles, R is gas constant, and T is temperature.
For a diatomic gas at room temperature, the degrees of freedom are:
- A. 5
- B. 3
- C. 6
- D. 7
Answer: A. 5
A diatomic gas has 3 translational and 2 rotational degrees of freedom (rotation about two axes perpendicular to molecular axis), totaling 5.
A diatomic gas has 3 translational and 2 rotational degrees of freedom (rotation about two axes perpendicular to molecular axis), totaling 5.
Which statement about the relationship between pressure and molecular kinetic energy is correct?
- A. Pressure is directly proportional to average kinetic energy of molecules
- B. Pressure is inversely proportional to average kinetic energy
- C. Pressure is independent of molecular kinetic energy
- D. Pressure depends only on the number of molecules, not their energy
Answer: A. Pressure is directly proportional to average kinetic energy of molecules
From kinetic theory, P = (1/3)ρ<c²> ∝ <KE>, showing direct proportionality between pressure and average molecular kinetic energy.
From kinetic theory, P = (1/3)ρ<c²> ∝ <KE>, showing direct proportionality between pressure and average molecular kinetic energy.
A sealed container with fixed volume contains a gas. If the molecular mass of the gas is doubled while keeping the number of molecules and temperature constant, the pressure will:
- A. Remain unchanged because PV = nRT and none of these change
- B. Increase by a factor of 2
- C. Decrease by a factor of √2
- D. Become indeterminate without knowing specific volume
Answer: A. Remain unchanged because PV = nRT and none of these change
Pressure from ideal gas law P = nRT/V depends only on n, R, T, and V—not on molecular mass. Molecular mass affects RMS speed but not pressure.
Pressure from ideal gas law P = nRT/V depends only on n, R, T, and V—not on molecular mass. Molecular mass affects RMS speed but not pressure.