If 1 mol of ice melts at its melting point of 273 K, the entropy change for the ice is 22.0 J/K. If the ice melts in someone's hand at 34°C, what is the change in the entropy of the universe? Assume a final temperature for the water of 0°C. The enthalpy of fusion for ice is 6.01 kJ/mol.

Question

Quizplus · Accepted Answer

The entropy change of the universe is the sum of the entropy change of the system (ice) and the surroundings (hand). The entropy change of the ice is 22.0 J/K. The entropy change of the surroundings is calculated as -ΔH/T, where ΔH is the enthalpy of fusion (6010 J) and T is the temperature of the surroundings in Kelvin (307 K). This gives -6010/307 = -19.6 J/K. The total change in entropy of the universe is 22.0 - 19.6 = +2.4 J/K.

If 1 Mol of Ice Melts at Its Melting Point