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DeltaH and DeltaS of a certain reaction ...

`DeltaH and DeltaS` of a certain reaction are -400 `kJ*mol^(-1) and -20kJ*mol^(-1)*K^(-1)` respectively. The temperature below which the reaction is spontaneous is-

A

100K

B

`20^(@)C`

C

`20K`

D

`120^(@)C`

Text Solution

Verified by Experts

The correct Answer is:
C
For a spontaneous reaction, `DeltaG=DeltaH-TDeltaS lt0`
`therefore TDeltaS gt DeltaH or, Tgt(DeltaH)/(DeltaS) or, T gt(400)/(20)K, or, T gt20K`
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