Thermodynamics (Chemical Perspective) – Multiple Choice Questions (MCQs)

1. 37. What is the van't Hoff equation used for?

   • A. To relate the equilibrium constant of a chemical reaction to temperature
   • B. To calculate reaction rates
   • C. To determine solubility
   • D. To calculate boiling points

2. 38. What is the Clausius-Clapeyron equation used for?

   • A. To relate the vapor pressure of a substance to its temperature
   • B. To calculate reaction rates
   • C. To determine solubility
   • D. To calculate boiling points

3. 39. What is Maxwell's relations in thermodynamics?

   • A. Equations that relate partial derivatives of thermodynamic properties
   • B. Equations for ideal gases
   • C. Equations for reaction kinetics
   • D. Equations for fluid flow

4. 40. What is residual property in thermodynamics?

   • A. The difference between the actual property of a real fluid and the property of an ideal gas at the same temperature and pressure
   • B. The property of a pure substance
   • C. The property at standard conditions
   • D. The property of a mixture

5. 41. What is Joule-Thomson effect?

   • A. The change in temperature of a real gas when it is allowed to expand at constant enthalpy
   • B. The change in temperature at constant volume
   • C. The change in pressure at constant temperature
   • D. The change in enthalpy at constant pressure

6. 42. What is the coefficient of performance (COP) for a refrigerator?

   • A. Q_L / W
   • B. Q_H / W
   • C. W / Q_L
   • D. W / Q_H

7. 43. What is the coefficient of performance (COP) for a heat pump?

   • A. Q_L / W
   • B. Q_H / W
   • C. W / Q_L
   • D. W / Q_H

8. 44. What is the Carnot cycle?

   • A. An ideal reversible thermodynamic cycle that describes the theoretical maximum efficiency of a heat engine or the theoretical maximum COP of a refrigerator/heat pump
   • B. A practical thermodynamic cycle
   • C. A cycle that only involves heat transfer
   • D. A cycle that only involves work

9. 45. What is the efficiency of a Carnot heat engine?

   • A. 1 - (T_C / T_H)
   • B. 1 - (T_H / T_C)
   • C. (T_H - T_C) / T_C
   • D. T_H / T_C

10. 46. What is the concept of exergy (availability)?

    • A. The maximum useful work that can be obtained from a system as it comes into equilibrium with its surroundings
    • B. A measure of wasted energy
    • C. The total energy of a system
    • D. The heat content of a system

11. 47. What is the phase rule for a non-reacting system?

    • A. F = C - P + 2
    • B. F = C - P + 1
    • C. F = C - P + 3
    • D. F = C + P - 2

12. 48. Which of the following is a state function?

    • A. Heat
    • B. Work
    • C. Internal Energy
    • D. Path Function