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Enthalpy of sublimation of a substance i...

Enthalpy of sublimation of a substance is equal to :

A

enthalpy of fusion `+` enthalpy of vaporisation

B

enthalpy of fusion

C

enthalpy of vaporisation

D

twice the enthalpy of vaporisation

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The correct Answer is:
B
Enthaply of sublimation of a substance is equal to enthalpy of fusion `+` enthalpy vaporisation.
Subimation is, direct conversion of solid to vapour. Solid `rarr` vapour
Writing in two steps, we have solid `rarr` liquid `rarr` vapour,
solid `rarr` liquid requires enthaply of fusion
liquid `rarr` vapour requires enthalpy of vaporisation
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