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JEE Main levelSingle correct optionDifficulty 2 of 3td194

For a gaseous reaction at $298 K$ , $Δ G^{\circ} = + 5.0 kJ mo l^{- 1}$ . In a mixture the reaction quotient is $Q = 0.010$ . Taking $R = 8.314 J mo l^{- 1} K^{- 1}$ , which statement is correct?

A $Δ G = + 5.00 kJ mo l^{- 1}$ ; the reaction does not proceed
B $Δ G = + 16.41 kJ mo l^{- 1}$ ; the reaction proceeds in reverse
C $Δ G = 0$ ; the system is at equilibrium
D $Δ G = - 6.41 kJ mo l^{- 1}$ ; the reaction proceeds forward

Answer: D

Δ G = Δ G^{\circ} + RT ln Q = 5000 + 8.314 \times 298 \times ln 0.010 = 5000 - 11410 = - 6410 J mo l^{- 1}

. A negative

Δ G

means the forward reaction is spontaneous even though

Δ G^{\circ} > 0

.

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