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For the reaction given below the value o...

For the reaction given below the value of standard Gibbs free energy of formation at 298 K are given. What is the nature of the reaction?
`I_(2)+H_(2)Srarr2HI+S`
`DeltaS_(f)^(@)(HI)="1.8 kJ mol"^(-1), DeltaG_(f)^(@)(H_(2)S)="33.8 kJ mol"^(-1)`

A

Non-spontaneous in forward direction.

B

Spontaneous in forward direction.

C

Spontaneous in backward direction.

D

Non-spontaneous in both forward and backward directions.

Text Solution

Verified by Experts

The correct Answer is:
B
`I_(2)+H_(2)S rarr 2HI +S`
`DeltaG^(@)=SigmaG_(f"(Products)")^(@)-SigmaG_(f"(Reactants)")^(@)`
`DeltaG^(@)=(2xx1.8+0)-(0+33.8)=-"30.2 kJ"`
Hence, reaction is spontaneous in forward direction.
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