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The enthalpy change for a given reaction...

The enthalpy change for a given reaction at `298 K` is `-x cal mol^(-1)`. If the reaction occurs spontaneously at `298 K`, the entropy change at that temperature

A

can be negative but numerically larger than `x//298 cal K^(-1)`

B

can be negative but numerically smaller than `x//298 cal K^(-1)`

C

cannot be negative

D

cannot be positive

Text Solution

Verified by Experts

The correct Answer is:
B

`DeltaG=DeltaH-T DeltaS`
For spontaneity, `DeltaG lt 0`
As `DeltaH= -xkcal` is negative and `T=298 K`. For `DeltaG` to be `lt 0`, `DeltaS` can be negative but numerically less than `x//298`.
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DINESH PUBLICATION-CHEMICAL THERMODYNAMICS AND CHEMICAL ENERGETICS -Exercise
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