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For the reaction at 298 K, 2A + B to ...

For the reaction at 298 K,
2A + B `to` C
`DeltaH=400 KJ mol^(-1) and DeltaS=0.2kJ K^(-1)mol^(-1)`
At what temperature will the reaction become spontaneous considering `DeltaH and DeltaS` o be constant over the temperature range.

Text Solution

Verified by Experts

When `DeltaG = 0` the reaction will be at equilibrium. The temperature at which the reaction is in equilibrium can be obtained as follows
`:.DeltaG = DeltaH -T DeltaS`
or `T = (DeltaH - DeltaG)/(DeltaS) = (400-0)/(0.2) = 2000 K`
The reaction will be spontaneous when `DeltaG` is negative. This is possible only at a temperature greater than 2000 K.
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