NEET UG 2006 — Chemistry Physical Chemistry

2006mcqeasy

Identify the correct statement for change of Gibbs energy for a system $\left(\Delta \mathrm{G}_{\text {system }}\right)$ at constant temperature and pressure:

Official previous-year question

Held on 30 Apr 2006 · Verified 9 Jul 2026.

Options

A
If $\Delta \mathrm{G}_{\text {system }} < 0$ , the process is not spontaneous
B
If $\Delta \mathrm{G}_{\text {system }}>0$ , the process is spontaneous
C
If $\Delta \mathrm{G}_{\text {system }}=0$ , the system has attained equilibrium
D
If $\Delta \mathrm{G}_{\text {system }}=0$ , the system is still moving in a particular direction

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Solution

If the Gibbs free energy for a system $\left(\Delta \mathrm{G}_{\text {system }}\right)$ is equal to zero, then the system is in equilibrium at constant temperature and pressure. Related Theory Free energy change criteria for predicting spontaneity is better than entropy change criteria because the former requires free energy change of system only whereas the latter requires entropy change of system and surroundings. $\Delta G>0$ ; the reaction is non-spontaneous and endergonic $\Delta G < 0 ;$ the reaction is spontaneous and exergonic $\Delta G=0 ;$ reaction is at equilibrium A Caution According to the second law of thermodynamics entropy of the universe always increases for a spontaneous process. $\Delta G$ determines the direction and extent of chemical change.

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Options

If $\Delta \mathrm{G}_{\text {system }} < 0$ , the process is not spontaneous

If $\Delta \mathrm{G}_{\text {system }}>0$ , the process is spontaneous

If $\Delta \mathrm{G}_{\text {system }}=0$ , the system has attained equilibrium

If $\Delta \mathrm{G}_{\text {system }}=0$ , the system is still moving in a particular direction

Solution

NEET UG 2006 — Chemistry Physical Chemistry

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NEET UG 2006 — Chemistry Physical Chemistry

Options

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Solution

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NEET UG Physical Chemistry in other years

More NEET UG Physical Chemistry questions

Other Chemistry topics for NEET UG

Organic Chemistry

Inorganic Chemistry

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