251. The shape of T-S diagram for Carnot Cycle is a
A. Rectangle
B. Rhombus
C. Trapezoid
D. Circle
✅ The correct answer is option A.
Thermodynamics MCQs
252. For a constant pressure reversible process, the enthalpy change (ΔH) of the system is
A. Cv.dT
B. Cp.dT
C. ∫Cp.dT
D. ∫Cv.dT
✅ The correct answer is option C.
253. Which of the following has the least thermal efficiency?
A. Steam engine
B. Carnot engine
C. Diesel engine
D. Otto engine
✅ The correct answer is option A.
254. With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure
A. Increases
B. Decreases
C. Remains same
D. Decreases linearly
✅ The correct answer is option A.
255. Pick out the extensive property out of the following.
A. Surface tension
B. Free energy
C. Specific heat
D. Refractive index
✅ The correct answer is option B.
256. During adiabatic expansion of gas
A. Pressure remains constant
B. Pressure is increased
C. Temperature remains constant
D. None of these
✅ The correct answer is option D.
257. Degress of freedom at triple point will be
A. 0
B. 1
C. 2
D. 3
✅ The correct answer is option A.
258. What happens in a reversible adiabatic compression?
A. Heating occurs
B. Cooling occurs
C. Pressure is constant
D. Temperature is constant
✅ The correct answer is option A.
259. The freezing point of a liquid decreases when the pressure is increased, if the liquid __________ while freezing.
A. Contracts
B. Expands
C. Does not change in volume
D. Either A, B or C
✅ The correct answer is option A.
260. Number of degrees of freedom for a three phase system in equilibrium comprising of three non-reacting chemical species is
A. 2
B. 0
C. 1
D. 3
✅ The correct answer is option A.