A. Expansion of an ideal gas against constant pressure
B. Atmospheric pressure vaporisation of water at 100°C
C. Solution of NaCl in water at 50°C
D. None of these
✅ The correct answer is option C.
Thermodynamics MCQs
362. Heat is added at constant temperature in an ideal __________ cycle.
A. Stirling
B. Brayton
C. Rankine
D. None of these
✅ The correct answer is option A.
363. For equilibrium process (i.e. reversible) in an isolated system
A. ds = 0
B. ds < 0
C. ds > 0
D. ds = Constant
✅ The correct answer is option A.
364. 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
✅ The correct answer is option C.
365. The expression for entropy change given by, ΔS = nR ln (V₂/V₁) + nCv ln (T₂/T₁) is valid for
A. Reversible isothermal volume change
B. Heating of a substance
C. Cooling of a substance
D. Simultaneous heating and expansion of an ideal gas
✅ The correct answer is option D.
366. The total change in the enthalpy of a system is independent of the
A. Number of intermediate chemical reactions involved
B. Pressure and temperature
C. State of combination and aggregation in the beginning and at the end of the reaction
D. None of these
✅ The correct answer is option A.
367. For a reversible process involving only pressure-volume work
A. (dF)T, p < 0
B. (dF)T, p > 0
C. (dF)T, p = 0
D. (dA)T, v < 0
✅ The correct answer is option C.
368. Heat is added at constant pressure in an ideal __________ cycle.
A. Stirling
B. Brayton
C. Rankine
D. Both B and C
✅ The correct answer is option D.
369. What is the ratio of adiabatic compressibility to isothermal compressibility?
A. 1
B. < 1
C. > 1
D. >> 1
✅ The correct answer is option B.
370. The energy of activation of exothermic reaction is
A. Zero
B. Negative
C. Very large compared to that for en-dothermic reaction
D. Not possible to predict
✅ The correct answer is option D.