Physics

Thermodynamics and Gas Laws

616 Questions

Thermodynamics and gas laws questions test the understanding of ideal gas behavior, work done during thermodynamic processes, and specific heat ratios. Key areas include isothermal, adiabatic, and isobaric expansions along with real gas deviations. These mathematical physics concepts are standard in engineering and general science competitive exams.

Ideal gas equationIsothermal and adiabatic processesThermodynamic workGas kinetic theoryReal gas behavior

Thermodynamics and Gas Laws Questions

Multiple choice

What does Graham's law of diffusion state?

  1. It states that at constant temperature and pressure, the rate of diffusion of a gas is inversely proportional to the square root of its density.

  2. Equal volumes of all gases at the same temperature and pressure have the same number of molecules.

  3. At constant pressure, the volume of a given mass of gas is directly proportional to the absolute temperature.

  4. At constant temperature, the volume of a given mass of a gas is inversely proportional to pressure.

  5. -
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

It is true about Graham's law.

Multiple choice

Which of the following statements is correct?

  1. One gas is ideal in all the real gases present.

  2. Helium and hydrogen are ideal gases.

  3. Ideal gas is an imaginary gas.

  4. Ideal gas can be liquefied by lowering the temperature and increasing the pressure.

  5. -
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This statement is true.

Multiple choice

Which of the following statements is/are incorrect?

a. Horizontal distribution of pressure is studied by drawing isobars at constant levels. b. Sea level pressure belts are considered constant and are used for measuring horizontal distribution of pressure. c. The horizontal distribution of pressure oscillates with the apparent movement of the Sun.

  1. a and b

  2. a and c

  3. only c

  4. Only b

  5. a, b and c
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This statement is incorrect. The sea level pressure belts are not constant as they oscillate with the movement of the sun. Horizontal distribution of pressure is studied by drawing isobars at constant levels. In order to eliminate the effect of altitude on pressure, it is measured at any station after being reduced to sea level for purposes of comparison.

Multiple choice

Which of the following statements is wrong about kinetic theory of gases. A. Heavier molecules transfer more momentum to the walls of the container. B. Between collisions, the molecules move in zig-zag lines with different velocity. C. Large number of molecules have very high velocity. Chose the correct code given below:

  1. A and B

  2. A and C

  3. B and C

  4. A, B and C

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Wrong statement for kinetic theory of gases: B. Between collisions, the molecules move in zig-zag lines with different velocity. Between collisions, the molecules move in straight lines with constant velocity. Wrong statement for kinetic theory of gases: A. Large number of molecules have very high velocity. Small number of molecules have very high velocity.

Multiple choice

In which of the following conditions, a process carried out at constant temperature and pressure will be spontaneous for all temperatures?

  1. ΔS positive, ΔH negative
  2. ΔS positive, ΔH positive
  3. ΔS negative, ΔH negative
  4. ΔS negative, ΔH positive

  1. Only 1

  2. 1 and 2

  3. 2 and 3

  4. 3 and 4

  5. Only 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A process carried out at constant temperature and pressure will be spontaneous only if ΔG is negative. ΔG = ΔH - T ΔS If ΔS is positive and ΔH is negative, then ΔG will be negative at all temperatures. Hence, the process will be spontaneous at all temperatures.

Multiple choice

Boyl' s law is a relationship between

  1. Pressure and volume

  2. Volume and temperature

  3. Volume and density

  4. Pressure and temperature
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Boyle's Law states that for a fixed amount of gas at constant temperature, pressure is inversely proportional to volume (P1V1 = P2V2). Volume and temperature relationship is Charles's Law. Volume and density are not directly related by Boyle's Law. Pressure and temperature relationship is Gay-Lussac's Law.

Multiple choice

Which of the following states Boyle's law correctly?

  1. Temperature remaining constant, the volume of a given mass of any gas is inversely proportional to its pressure

  2. The volume of a given mass of any gas is directly proportional to the product of its temperature and pressure

  3. Volume and temperature remaining constant, the mass of any gas inversely proportional to its pressure

  4. Temperature remaining constant, the volume of a given mass of any gas is directly proportional to its pressure
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Boyle's law states that for a fixed mass of gas at constant temperature, pressure is inversely proportional to volume (P ∝ 1/V or PV = constant). This means as pressure increases, volume decreases proportionally, and vice versa. Option A correctly states this inverse relationship with the condition of constant temperature.

Multiple choice

Henry's law is for

  1. a solution of a gas in a gas

  2. a solution of a gas in a liquid

  3. a solution of a liquid in a liquid

  4. a solution of a solid in a liquid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Henry's law is for a solution of a gas in a liquid.

Multiple choice

In Langmuir's model of adsorption of a gas on a solid surface:

  1. the rate of dissociation of adsorbed molecules from the surface does not depend on the surface covered

  2. the adsorption at a single site on the surface may involve multiple molecules at the same time

  3. the mass of gas striking a given area of surface is proportional to the pressure of the gas

  4. the mass of gas striking a given area of surface is independent of the pressure of the gas
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the Langmuir adsorption isotherm, the rate of gas molecules striking the surface is directly proportional to the pressure of the gas.