August 2022

Question: It is desired to bring about a certain change in the state of a system by performing work on the system under adiabatic conditions.
[A].

The amount of work needed is path dependent.

[B].

Work alone can not bring out such a change of state.

[C].

The amount of work needed is independent of path.

[D].

More information is needed to conclude anything about the path dependence or otherwise of the work needed.

Answer: Option A

Explanation:

No answer description available for this question.

Question: A change in state involving a decrease in entropy can be spontaneous, only if
[A].

it is exothermic.

[B].

it is isenthalpic.

[C].

it takes place isothermally.

[D].

it takes place at constant volume.

Answer: Option A

Explanation:

No answer description available for this question.

Question: A system undergoes a change from a given initial state to a given final state either by an irreversible process or by a reversible process, then(where, Δ S1 and Δ SR are the entropy changes of the system for the irreversible and reversible processes respectively)
[A].

Δ S1 is always < Δ SR

[B].

Δ S1 is sometimes > Δ SR

[C].

Δ S1 is always > Δ SR

[D].

Δ S1 is always = Δ SR

Answer: Option C

Explanation:

No answer description available for this question.

Question: A closed system is cooled reversibly from 100°C to 50°C. If no work is done on the system
[A].

its internal energy (U) decreases and its entropy (S) increases.

[B].

U and S both decreases

[C].

U decreases but S is constant.

[D].

U is constant but S decreases.

Answer: Option B

Explanation:

No answer description available for this question.

Question: In any spontaneous process, the __________ free energy decreases.
[A].

Helmholtz

[B].

Gibbs

[C].

both a & b

[D].

neither ‘a’ nor ‘b’

Answer: Option C

Explanation:

No answer description available for this question.

Question: Entropy change of the reaction, H2O(liquid) H2O(gas), is termed as the enthalpy of
[A].

solution

[B].

vaporisation

[C].

formation

[D].

formation

Answer: Option B

Explanation:

No answer description available for this question.

Question: Partial molar free energy of an element A in solution is same as its
[A].

chemical potential

[B].

activity

[C].

fugacity

[D].

activity co-efficient

Answer: Option A

Explanation:

No answer description available for this question.

Question: During Joule-Thomson expansion of gases
[A].

enthalpy remains constant.

[B].

entropy remains constant.

[C].

temperature remains constant.

[D].

none of these.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Gibbs phase rule finds application, when heat transfer occurs by
[A].

conduction

[B].

convection

[C].

radiation

[D].

condensation

Answer: Option D

Explanation:

No answer description available for this question.

Question: Change of state namely evaportation condensation, freezing and melting is an __________ process.
[A].

isothermal

[B].

adiabatic

[C].

isobaric

[D].

isochoric

Answer: Option A

Explanation:

No answer description available for this question.