The enthalpy of vaporisation of a liquid is `30 kJ mol^(-1)` and entropy of vaporisation is `75 J mol^(-1) K^(-1)`. The boiling point of the liquid at `1atm` is :A. `250 K`B. `400 K`C. `450 K`D. `600 K`

The enthalpy of vaporisation of a liquid is `30 kJ mol^(-1)` and entro

1.	The enthalpy of vaporisation of a liquid is `30 kJ mol^(-1)` and entropy of vaporisation is `75 J mol^(-1) K^(-1)`. The boiling point of the liquid at `1atm` is :A. `250 K`B. `400 K`C. `450 K`D. `600 K`
Answer» Correct Answer - B `DeltaH=30 kJ mol^(-1)=30,000 J mol^(-1)` `DeltaS=75 J mol^(-1)K^(-1)` At boiling point, the reversible process `"liquid" hArr "vapour"` is in equilibrium at one atmospheric pressure `:. DeltaG=0` `DeltaG=DeltaH-TDeltaS` `:. T=(DeltaH)/(DeltaS)=(30,000 Jmol^(-1))/(75 J mol^(-1)K^(-1))=400 K`

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The enthalpy of vaporisation of a liquid is `30 kJ mol^(-1)` and entropy of vaporisation is `75 J mol^(-1) K^(-1)`. The boiling point of the liquid at `1atm` is :A. `250 K`B. `400 K`C. `450 K`D. `600 K`

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