Thermal Properties of Matter MCQs for NEET — Physics Questions with Answers

The NCERT text (Chapter: KINETIC_THEORY, Section 12.4.2) states, 'the average kinetic energy of a molecule is proportional to the absolute temperature of the gas [from E/N = (1/2)m <v^2> = (3/2)k_B T]'. This is a fundamental result.

The NCERT text (Chapter: KINETIC_THEORY, Section 12.3) mentions, 'the total pressure of a mixture of ideal gases is the sum of partial pressures.' This is also known as Dalton's Law of Partial Pressures.

The NCERT text (Chapter: KINETIC_THEORY, Summary point 1) directly gives the relation: $k_B = R/N_A$.

The NCERT text (Chapter: THERMODYNAMICS_Physics, Section 11.7 and Section 6 of point list) explicitly states, 'Examples of state variables are pressure (P ), volume (V ), temperature (T ), and mass (m ). Heat and work are not state variables.'

The NCERT text (Chapter: KINETIC_THEORY, Section 12.4.2) states, 'internal energy of an ideal gas depends only on temperature, not on pressure or volume.' This is also implied when discussing $C_v$ in Chapter: THERMODYNAMICS_Physics, Section 11.7, where U of an ideal gas depends only on temperature.

The NCERT text (Chapter: KINETIC_THEORY, Section 12.3) mentions, 'Once again you see that the agreement is good at high temperatures and low pressures' when comparing experimental P-V curves with Boyle's law.

The NCERT text (Chapter: KINETIC_THEORY, Summary point 1) gives the ideal gas equation as PV = µRT = k_B N T. Therefore, N k_B T represents the product of pressure and volume (PV).

The NCERT text (Chapter: KINETIC_THEORY, Summary point 2) states, 'In a mixture of gases at a fixed temperature the heavier molecule has the lower average speed.' This is because the average kinetic energy ($1/2 m v^2$) is the same for all molecules at a given temperature, so if 'm' is larger, 'v' must be smaller.

The NCERT text states: 'According to Newton’s law of cooling, the rate of loss of heat, $-dQ/dt$ of the body is directly proportional to the difference of temperature $\Delta T = (T_2 - T_1)$ of the body and the surroundings.'

The text explicitly mentions: 'The law holds good only for small difference of temperature.'