A. Increases with increase in pressure
B. Decreases with increase in temperature
C. Is independent of temperature
D. None of these
✅ The correct answer is option D.
Chemical Engineering MCQs
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
✅ The correct answer is option D.
Fugacity of a component in an ideal gas mixture is euqal to the partial pressure of that component in the mixture. The fugacity of each component in a stable homogeneous solution at contant pressure and temperature __________ as its mole fraction increases.
A. Decreases
B. Decreases exponentially
C. Increases
D. Remains constant
✅ The correct answer is option C.
The Joule-Thomson co-efficient is defined as (∂T/∂P)H. Its value at the inversion point is
A. ∞
B. 1
C. 0
D. -ve
✅ The correct answer is option C.
Cp – Cv = R is valid for __________ gases.
A. Ideal
B. All
C. Very high pressure
D. Very low temperature
✅ The correct answer is option A.
Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is
A. 300(32/7)
B. 300(33/5)
C. 300(33/7)
D. 300(35/7)
✅ The correct answer is option A.
In a reversible chemical reaction (where, Δx = number of moles of products-number of moles of reactants )
A. Addition of inert gas favours the forward reaction, when Δx is positive
B. Pressure has no effect on equilibrium, when Δn = 0
C. Addition of inert gas has no effect on the equilibrium constant at constant volume for any value of Δx (+ ve, – ve) or zero)
D. All of the above
✅ The correct answer is option D.
In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process.
A. Isothermal
B. Adiabatic
C. Isentropic
D. Polytropic
✅ The correct answer is option C.
The expression for entropy change, ΔS = n Cp . ln (T₂/T₁), is valid for the __________ of a substance.
A. Simultaneous pressure & temperature change
B. Heating
C. Cooling
D. Both B and C
✅ The correct answer is option D.
Entropy change of mixing two liquid substances depends upon the
A. Molar concentration
B. Quantity (i.e. number of moles)
C. Both A and B
D. Neither A nor B
✅ The correct answer is option C.