Question

Calculate the change in entropy for fusion of 1 mole of ice. The melting point of ice is 273 K and molar enthalpy of fusion for ice = 6.0 kJ $mol{e}^{-1}$

• A. ∆Sf=21.97 JK^-1 mol^-1
• B. ∆Sf=21.87 JK¹ mol^-1
• C. ∆Sf=21.78 JK^-1 mol^-1
• D. ∆Sf=21.79 JK^-1 mol^-1

Answer 1

The correct option is A

∆Sf=21.97 JK^-1 mol^-1

For entropy change of fusion we know that the entropy change is given by, $\Delta S_f=\Delta \frac{H_f}{T}$
Given values are, $\Delta H_f=6\times {10}^{3}Jmo{l}^{-1}$; T=273K
Therefore $\Delta S_f=(6\times \frac{{10}^3}{273})$
$\Delta S_f$ =21.97 $J{K}^{-1}mo{l}^{-1}$