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One mole of a substance is cooled at the...

One mole of a substance is cooled at the rate of `0.4 kJ min^(-1)` as shown in the graph. Curve `AB`, points `B` and `C` and curve `CD` represent respectively, the cooling of the liquid, start of freezing, completion of freezing and cooling of the solid based on this data. The entropy of fusion in `J molK^(-1)` is :

A

`10`

B

`20`

C

`30`

D

`40`

Text Solution

Verified by Experts

The correct Answer is:
C
The cooling shows fusion process for `30` minute `(40-10)` at `400K`
`DeltaS=q/T=(0.4xx10^(3)xx30)/400=30 J`
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