111. Adiabatic compression of a saturated water vapour makes it
A. Supersaturated
B. Superheated
C. Both A and B
D. Neither A nor B
✅ The correct answer is option B.
Thermodynamics MCQs
112. In an adiabatic process, the
A. Heat transfer is zero
B. Temperature change is zero
C. Work done is a path function
D. Enthalpy remains constant
✅ The correct answer is option A.
113. A refrigerator may be termed as a
A. Heat pump
B. Heat engine
C. Carnot engine
D. None of these
✅ The correct answer is option A.
114. The second law of thermodynamics states that
A. The energy change of a system undergoing any reversible process is zero
B. It is not possible to transfer heat from a lower temperature to a higher temperature
C. The total energy of system and surrounding remains the same
D. None of the above
✅ The correct answer is option D.
115. Pick out the correct equation relating ‘F’ and ‘A’.
A. F = A + PV
B. F = E + A
C. F = A – TS
D. F = A + TS
✅ The correct answer is option A.
116. Specific volume of an ideal gas is
A. Equal to its density
B. The reciprocal of its density
C. Proportional to pressure
D. None of these
✅ The correct answer is option B.
117. For a constant volume process __________ by the system is used only to increase the internal energy.
A. Heat absorbed
B. Work done
C. Both A & B
D. Neither A nor B
✅ The correct answer is option A.
118. A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is Φi yi P = Yi xi fi° where, Φ is a vapor fugacity component, Yi is the liquid activity co-efficient and fi° is the fugacity of the pure component i. the Ki value (Yi = Ki xi) is therefore, in general a function of
A. Temperature only
B. Temperature and pressure only
C. Temperature, pressure and liquid composition xi only
D. Temperature, pressure, liquid composition xi and vapour composition yi
✅ The correct answer is option C.
119. Compressibility factor of a gas is
A. Not a function of its pressure
B. Not a function of its nature
C. Not a function of its temperature
D. Unity, if it follows PV = nRT
✅ The correct answer is option A.
120. A two stage compressor is used to compress an ideal gas. The gas is cooled to the initial temperature after each stage. The intermediate pressure for the minimum total work requirement should be equal to the __________ mean of P₁ and P₂.(where, P₁ and P₂ are initial and final pressures respectively)
A. Logarithmic
B. Arithmetic
C. Geometric
D. Harmonic
✅ The correct answer is option C.