Calculate the entropy change for melting 1 g ice at $0^{\circ} \mathrm{C}$ in $\mathrm{Jg}^{-1} \mathrm{~K}^{-1}$ if heat of fusion of ice at $0^{\circ} \mathrm{C}$ is $80 \mathrm{~J} \mathrm{~K}^{-1}$.

Question

Aicharya · Accepted Answer

For the reaction, $\mathrm{H}_2 \mathrm{O}_{(\mathrm{s})} \rightleftharpoons \mathrm{H}_2 \mathrm{O}_{(l)}$
The change in Gibbs energy at constant temperature and constant pressure is given by, $\Delta \mathrm{G}=\Delta \mathrm{H}-\mathrm{T} \Delta \mathrm{~S}$
At equilibrium, $\Delta \mathrm{G}=0$ $\therefore \quad \Delta \mathrm{S}=\frac{\Delta \mathrm{H}_{\text {fusion }}}{\mathrm{T}}=\frac{80}{273}=0.293\left(\because 0^{\circ} \mathrm{C}=273 \mathrm{~K}\right)$

Calculate the entropy change for melting 1 g ice at $0^{\circ} \mathrm{C}$ in $\mathrm{Jg}^{-1}…

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