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A certain reaction has a Delta H of 12 k...

A certain reaction has a `Delta H` of 12 kJ and a `Delta S` of 40 `"JK"^(-1)`. The temperature above which the reaction becomes spontaneous is

A

27°C

B

27 K

C

300°C

D

30°C

Text Solution

Verified by Experts

The correct Answer is:
A
A reaction will be spontaneous, if
`Delta H - T Delta S = -"ve" or "Delta H - T Delta S lt 0`
or `T lt (Delta H)/( Delta S)`
Now, `(Delta H)/( Delta S) = (12 xx 10^3)/( 40) = 300 "K"`
`therefore` Above `27^(@)`C, the reaction becomes spontaneous.
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Knowledge Check

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