Chemical Engineering Thermodynamics 1000+ MCQ with answer for SBI Clerk

1. If the pressure on 100 c.c. of air is halved, then its volume (at the same temperature) would be __________ c.c.
A. 100
B. 50
C. 205
D. 200
Answer : D

2. The principle applied in liquefaction of gases is
A. Adiabatic expansion
B. Joule-Thomson effect
C. Both (A) and (B)
D. Neither (A) nor (B)
Answer : C

3. The intensive properties are
A. Molar volume, density, viscosity and boiling point
B. Refractive index and surface tension
C. Both (A) and (B)
D. None of these
Answer : C

4. Claude's liquefaction process employs the cooling of gases by
A. Expansion in an engine
B. Following a constant pressure cycle
C. Throttling
D. None of these
Answer : A

5. The Carnot co-efficient of performance (COP) of a domestic air conditioner compared to a household refrigerator is
A. Less
B. More
C. Same
D. Dependent on climatic conditions
Answer : A

6. When liquid and vapour phase of multi-component system are in equilibrium (at a given temperature and pressure), then chemical potential of each component is
A. Same in both the phases
B. Zero in both the phases
C. More in vapour phase
D. More in liquid phase
Answer : A

7. Equilibrium constant decreases as the temperature
A. Increases, for an exothermic reaction
B. Decreases, for an exothermic reaction
C. Increases, for an endothermic reaction
D. None of these
Answer : A

8. 4 kg moles of an ideal gas expands in vacuum spontaneously. The work done is
A. 4 J
B. ?
C. 0
D. 8 J
Answer : C

9. For an isothermal reversible compression of an ideal gas
A. Only ?E = 0
B. Only ?H =0
C. ?E = ?H = 0
D. dQ = dE
Answer : C

10. Vapour which is at a pressure smaller than the saturation pressure for the temperature involved is called a __________ vapour.
A. Superheated
B. Desuperheated
C. Non-condensable
D. None of these
Answer : A

11. First law of thermodynamics deals with the
A. Direction of energy transfer
B. Reversible processes only
C. Irreversible processes only
D. None of these
Answer : A

12. Work done may be calculated by the expression ? p dA for __________ processes.
A. Non-flow reversible
B. Adiabatic
C. Both (A) and (B)
D. Neither (A) nor (B)
Answer : C

13. Entropy change for an irreversible process taking system and surrounding together is
A. 0
B. > 0
C. < 0
D. None of these
Answer : B

14. If two pure liquid constituents are mixed in any proportion to give an ideal solution, there is no change in
A. Volume
B. Enthalpy
C. Both (A) & (B)
D. Neither (A) nor (B)
Answer : C

15. The specific heat of saturated water vapour at 100°C is
A. ?
B. -ve
C. 0
D. +ve
Answer : B

16. Fugacity and pressure are numerically not equal for the gases
A. At low temperature and high pressure
B. At standard state
C. Both (A) and (B)
D. In ideal state
Answer : C

17. For an ideal liquid solution, which of the following is unity?
A. Activity
B. Fugacity
C. Activity co-efficient
D. Fugacity co-efficient
Answer : C

18. Number of degrees of freedom for a three phase system in equilibrium comprising of three nonreacting chemical species is
A. 2
B. 0
C. 1
D. 3
Answer : A

19. On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will
A. Increase
B. Decrease
C. Remain same
D. Increase in summer and will decrease in winter
Answer : A

20. Compressibility factor (i.e., the ratio of actual volume of gas to the volume predicted by ideal gas law) for all gases are
A. Always greater than one
B. Same at the same reduced temperature
C. Same at the same reduced pressure
D. Both (B) & (C)
Answer : D

21. Free energy change at equilibrium is
A. Zero
B. Positive
C. Negative
D. Indeterminate
Answer : A

22. The value of Joule-Thomson co-efficient, in case where cooling occurs after the throttling process is
A. 0
B. ?
C. +ve
D. -ve
Answer : C

23. Extensive properties of a thermodynamic system depend upon the __________ of the system.
A. Specific volume
B. Temperature
C. Mass
D. Pressure
Answer : C

24. The internal energy of a gas obeying P (V - b) RT (where, b is a positive constant and has a constant C_v), depends upon its
A. Pressure
B. Volume
C. Temperature
D. All (A), (B) & (C)
Answer : C

25. In the reaction; N₂ + O₂ ? 2NO, increasing the pressure will result in
A. Shifting the equilibrium towards right
B. Shifting the equilibrium towards left
C. No change in equilibrium condition
D. None of these
Answer : C

26. Boiling of liquid is accompanied with increase in the
A. Vapor pressure
B. Specific Gibbs free energy
C. Specific entropy
D. All (A), (B) and (C)
Answer : A

27. The internal energy of an ideal gas is a function of its __________ only.
A. Molecular size
B. Volume
C. Pressure
D. Temperature
Answer : D

28. An isentropic process is carried out at constant
A. Volume
B. Pressure
C. Temperature
D. All (A), (B) and (C)
Answer : A

29. If the internal energy of an ideal gas decreases by the same amount as the work done by the system, then the
A. Process must be isobaric
B. Temperature must decrease
C. Process must be adiabatic
D. Both (B) and (C)
Answer : D

30. The reaction A (l) ? R(g) is allowed to reach equilibrium conditions in an autoclave. At equilibrium, there are two phases, one a pure liquid phase of A and the other a vapor phase of A, R and S. Initially A alone is present. The numbers of degrees of freedom are:
A. 1
B. 2
C. 3
D. 0
Answer : B

31. Which one is true for a throttling process?
A. A gas may have more than one inversion temperatures
B. The inversion temperature is different for different gases
C. The inversion temperature is same for all gases
D. The inversion temperature is the temperature at which Joule-Thomson co-efficient is infinity
Answer : B

32. Entropy is a/an
A. State function
B. Macroscopic property
C. Extensive property
D. None of these
Answer : D

33. The expression for the work done for a reversible polytropic process can be used to obtain the expression for work done for all processes, except reversible __________ process.
A. Isobaric
B. Isothermal
C. Adiabatic
D. None of these
Answer : B

34. Pick out the wrong statement.
A. An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law
B. If Raoult's law is applied to one component of a binary mixture; Henry's law or Raoult's law is applied to the other component also
C. Henry's law is rigorously correct in the limit of infinite dilution
D. None of these
Answer : D

35. Which is a state function?
A. Specific volume
B. Work
C. Pressure
D. Temperature
Answer : B

36. Third law of thermodynamics is helpful in
A. Prediction of the extent of a chemical reaction
B. Calculating absolute entropies of substances at different temperature
C. Evaluating entropy changes of chemical reaction
D. Both (B) and (C)
Answer : D

37. The ratio of equilibrium constants (Kp2/Kp1) at two different temperatures is given by
A. (R/?H) (1/T₁ - 1/T₂)
B. (?H/R) (1/T₁ - 1/T₂)
C. (?H/R) (1/T₂ - 1/T₁)
D. (1/R) (1/T₁ - 1/T₂)
Answer : B

38. In the reaction, C + O₂ ? CO₂; ?H = - 94 kcal. What is the heat content (enthalpy) of O₂?
A. -94 kcal
B. > -94 kcal
C. < - 94 kcal
D. Zero
Answer : D

39. Measurement of thermodynamic property of temperature is facilitated by __________ law of thermodynamics.
A. 1st
B. Zeroth
C. 3rd
D. None of these
Answer : B

40. Efficiency of a heat engine working on Carnot cycle between two temperature levels depends upon the
A. Two temperatures only
B. Pressure of working fluid
C. Mass of the working fluid
D. Mass and pressure both of the working fluid
Answer : A

41. C_p of a gas at its critical temperature and pressure
A. Becomes zero
B. Becomes infinity
C. Equals 1 kcal/kmol °K
D. Equals 0.24 kcal/kmol °K
Answer : B

42. The unity of Planck's constant 'h' in the equation, E = hv is
A. J/s
B. J.S
C. J/kmol
D. kmol/J
Answer : B

43. Heat is added at constant temperature in an ideal __________ cycle.
A. Stirling
B. Brayton
C. Rankine
D. None of these
Answer : A

44. For an ideal gas, the activity co-efficient is
A. Directly proportional to pressure
B. Inversely proportional to pressure
C. Unity at all pressures
D. None of these
Answer : C

45. The shape of T-S diagram for Carnot Cycle is a
A. Rectangle
B. Rhombus
C. Trapezoid
D. Circle
Answer : A

46. Co-efficient of Performance (COP) of a refrigerator is the ratio of the
A. Work required to refrigeration obtained
B. Refrigeration obtained to the work required
C. Lower to higher temperature
D. Higher to lower temperature
Answer : B

47. Critical solution temperature (or the consolute temperature) for partially miscible liquids (e.g., phenol-water) is the minimum temperature at which
A. A homogeneous solution (say of phenol water) is formed
B. Mutual solubility of the two liquids shows a decreasing trend
C. Two liquids are completely separated into two layers
D. None of these
Answer : A

48. The absolute entropy for all crystalline substances at absolute zero temperature is
A. Zero
B. Negative
C. More than zero
D. Indeterminate
Answer : A

49. The value of C_p & C_v respectively for monatomic gases in Kcal/kg Mole.°K are
A. 5 & 3
B. 3.987 & 1.987
C. 1.987 & 0.66
D. 0.66 & 1.987
Answer : A

50. For an incompressible fluid, the __________ is a function of both pressure as well as temperature.
A. Internal energy
B. Enthalpy
C. Entropy
D. All (A), (B) & (C)
Answer : B