Question

For a phase change, (Δ H^0 = 31 , {kJ/mol}) and (Δ S^0 = 0.093 , {kJ/(K·mol)}). What are (Δ G) and the spontaneity of the phase change at 300 K?

Answer 1

The Gibbs free energy (ΔG) for the phase change at 300 K is calculated to be 3.1 kJ/mol, indicating that the phase change is nonspontaneous under standard conditions.

Step-by-step explanation:

For a phase change with ΔH° = 31 kJ/mol and ΔS° = 0.093 kJ/(K·mol), we can calculate the Gibbs free energy (ΔG) at a temperature (T) of 300 K using the Gibbs free energy equation: ΔG = ΔH° - T·ΔS°. Substituting the values, we get:

ΔG = 31 kJ/mol - (300 K · 0.093 kJ/(K·mol))

ΔG = 31 kJ/mol - 27.9 kJ/mol

ΔG = 3.1 kJ/mol

Since ΔG > 0, the phase change is nonspontaneous at 300 K under standard conditions.