Chemical Engineering Thermodynamics MCQs

Question 1

Gibbs-Duhem equation

Accepted Answer

States that n1dμ1 + n2dμ2 + .... njdμj = 0, for a system of definite composition at constant temperature and pressure

Answer

Applies only to binary systems

Answer

Finds no application in gas-liquid equilibria involved in distillation

Answer

None of these

Question 2

Pick out the correct statement.

Accepted Answer

All of the above

Answer

The available energy in an isolated system for all irreversible (real) processes decreases

Answer

The efficiency of a Carnot engine increases, if the sink temperature is decreased

Answer

The reversible work for compression in non-flow process under isothermal condition is the change in Helmholtz free energy

Question 3

The unity of Planck's constant 'h' in the equation, E = hv is

Accepted Answer

J.S

Answer

J/s

Answer

J/kmol

Answer

Kmol/J

Question 4

For the reversible exothermic reaction, N2 + 3H2 ⇋ 2NH3, increase of pressure would

Accepted Answer

Both A and B

Answer

Shift the equilibrium towards right

Answer

Give higher yield of NH3

Answer

Neither A nor B

Question 5

If heat contents of CH4, C2H4 and C3H8 are -17.9, 12.5 and -24.8 kcal/mole respectively, than ΔH for the reaction CH4(g) + C2H4(g) ⇋ C3H8(g) will be __________ Kcal.

Accepted Answer

-19.4

Answer

-30.2

Answer

55.2

Answer

-55.2

Question 6

Pick out the wrong statement.

Accepted Answer

A refriferation cycle violates the second law of thermadynamics

Answer

Refrigeration cycle is normally represented by a temperature vs. entropy plot

Answer

In a refrigerator, work required decreases as the temperature of the refrigerator and the temperature at which heat is rejected increases

Answer

One ton of refrigeration is equivalent to the rate of heat absorption equal to 3.53 kW

Question 7

The work done in an adiabatic change in a particular gas depends upon changes in the __________ only.

Accepted Answer

Temperature

Answer

Specific heat

Answer

Volume

Answer

Pressure

Question 8

The expression, nCv(T2 - T1), is for the __________ of an ideal gas.

Accepted Answer

Work done under adiabatic condition

Answer

Co-efficient of thermal expansion

Answer

Compressibility

Answer

None of these

Question 9

The chemical potential of any constituent of an ideal solution depends on the __________ of the solution.

Accepted Answer

All of the above

Answer

Temperature

Answer

Pressure

Answer

Composition