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One gram of an organic liquid X (molecul...

One gram of an organic liquid X (molecular mass 78) liberates 160 J of heat on solidification. `Delta H_("fusion")(X)` is :

A

`19.2kJ//mol`

B

`12.48kJ//mol`

C

`124.8kJ//mol`

D

None of these

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The correct Answer is:
2
For 1g liberates `160J" ":. 78g` liberates `160xx78=1280J //mol=12.480kJ//mol`
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