Answer:
1.75 J/K.
Explanation:
Using Gibbs free energy equation,
ΔG = ΔH - TΔS
Where,
ΔG = free energy
ΔH = enthalpy change
T = absolute temperature
ΔS = entropy change
Note: ΔG of fusion =0
Therefore,
ΔH = TΔS,
ΔS = ΔH/T
Given:
T = °C + 273.15
= 273.15 + 69
= 342.15 K
n = 0.25 mol.
ΔH = 2.39 kJ/mol
= 2.39 / 342.15
= 6.99 J/Kmol
ΔS = ΔSmolar * n
= 6.99 * 0.25
= 1.75 J/K.
