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1. The first law of thermodynamics is a statement of the conservation of

A. Momentum B. Energy C. Mass D. Charge

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2. In an isothermal process, the change in internal energy of an ideal gas is

A. Positive B. Negative C. Zero D. Depends on the process

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3. The efficiency of a Carnot engine operating between temperatures T₁ and T₂ (T₁ > T₂) is given by

A. 1 - T₂/T₁ B. T₂/T₁ C. 1 - T₁/T₂ D. T₁/T₂

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4. The process in which no heat is exchanged with the surroundings is called

A. Isothermal B. Adiabatic C. Isobaric D. Isochoric

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5. The specific heat capacity at constant volume (C_v) for an ideal gas is related to the specific heat capacity at constant pressure (C_p) by

A. C_p = C_v + R B. C_p = C_v - R C. C_p = C_v D. C_p = R/C_v

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6. The work done by an ideal gas during an isochoric process is

A. Positive B. Negative C. Zero D. Depends on the process

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7. The internal energy of an ideal gas depends on

A. Pressure only B. Volume only C. Temperature only D. Temperature and pressure

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8. In a cyclic process, the net change in internal energy of the system over one complete cycle is

A. Positive B. Negative C. Zero D. Depends on the process

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9. The second law of thermodynamics introduces the concept of

A. Internal energy B. Enthalpy C. Entropy D. Work

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10. For a spontaneous process, the change in Gibbs free energy (ΔG) is

A. Positive B. Negative C. Zero D. Depends on the process

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11. The enthalpy change (ΔH) of a system is equal to the heat exchanged at constant

A. Volume B. Pressure C. Temperature D. Entropy

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12. The ratio of the specific heats (γ = C_p/C_v) for a monoatomic ideal gas is

A. 1.33 B. 1.4 C. 1.67 D. 2.0

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13. During an adiabatic expansion of an ideal gas, the temperature of the gas

A. Increases B. Decreases C. Remains constant D. First increases, then decreases

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14. The Helmholtz free energy (F) is defined as

A. F = U - TS B. F = H - TS C. F = U + TS D. F = H + TS

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15. The Maxwell's relations are derived from

A. First law of thermodynamics B. Second law of thermodynamics C. Third law of thermodynamics D. Fundamental thermodynamic equations

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16. The Clausius statement of the second law of thermodynamics implies that

A. Heat cannot spontaneously flow from a colder body to a hotter body B. Heat cannot spontaneously flow from a hotter body to a colder body C. No process is 100% efficient D. Entropy of the universe is always increasing

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17. The Joule-Thomson effect describes the change in temperature of a real gas when it

A. Expands adiabatically B. Is compressed isothermally C. Expands through a porous plug D. Is compressed adiabatically

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18. The critical point of a substance is the point at which

A. Solid, liquid, and gas phases coexist in equilibrium B. Liquid and gas phases become indistinguishable C. Solid and liquid phases become indistinguishable D. None of the above

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19. The heat capacity of a substance is defined as

A. The amount of heat required to raise the temperature of the substance by one degree Celsius B. The amount of heat required to raise the temperature of one mole of the substance by one degree Celsius C. The amount of heat required to raise the temperature of one gram of the substance by one degree Celsius D. The amount of heat required to change the phase of the substance

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20. The third law of thermodynamics states that

A. The entropy of a perfect crystal approaches zero as the temperature approaches absolute zero B. The entropy of the universe is always increasing C. Energy cannot be created or destroyed D. No process is 100% efficient