The enthalpy of fusion for benzene is 127.40 kJ/kg, and its melting point is 5.5°C. What is the entropy change when 1 mole of benzene melts at 5.5°C?

Question

Quizplus · Accepted Answer

The entropy change (ΔS) can be calculated using the formula ΔS = ΔH/T, where ΔH is the enthalpy change and T is the temperature in Kelvin. First, convert the melting point to Kelvin (5.5°C = 278.65 K). The molar mass of benzene is 78.11 g/mol, so the enthalpy of fusion per mole is (127.40 kJ/kg) * (78.11 g/mol) / 1000 = 9.95 kJ/mol. Then, ΔS = 9.95 kJ/mol / 278.65 K = 0.0357 kJ/K = 35.7 J/K.

The Enthalpy of Fusion for Benzene Is 127