A. ∞
B. + ve
C. 0
D. -ve
✅ The correct answer is option C.
Thermodynamics MCQs
As pressure approaches zero, the ratio of fugacity to pressure (f/P) for a gas approaches
A. Zero
B. Unity
C. Infinity
D. An indeterminate value
✅ The correct answer is option B.
__________ does not change during phase transformation processes like sublimation, melting & vaporisation.
A. Entropy
B. Gibbs free energy
C. Internal energy
D. All of the above
✅ The correct answer is option B.
Heat of formation of an element in its standard state is
A. 0
B. < 0
C. > 0
D. A function of pressure
✅ The correct answer is option A.
Specific __________ does not change during phase change at constant temperature and pressure.
A. Entropy
B. Gibbs energy
C. Internal energy
D. Enthalpy
✅ The correct answer is option B.
Filling of gas from a high pressure cylinder into small bottles is an example of a/an __________ process.
A. Equilibrium
B. Adiabatic
C. Steady
D. Unsteady
✅ The correct answer is option D.
Free energy
A. Decreases in all spontaneous (or irreversible) processes
B. Change during a spontaneous process has a negative value
C. Remains unchanged in reversible processes carried at constant temperature and pressure
D. All of the above
✅ The correct answer is option D.
Which of the following is a widely used refrigerant in vapour compression refrigeration system (using large centrifugal compressor)?
A. Freon
B. Liquid sulphur dioxide
C. Methyl chloride
D. Ammonia
✅ The correct answer is option A.
Work done in an adiabatic process between two states depends on the
A. Rate of heat transmission
B. Initial state only
C. End states only
D. None of these
✅ The correct answer is option C.
One mole of nitrogen at 8 bar and 600 K is contained in a piston-cylinder arrangement. It is brought to 1 bar isothermally against a resisting pressure of 1 bar. The work done (in Joules) by the gas is
A. 30554
B. 10373
C. 4988.4
D. 4364.9
✅ The correct answer is option B.