Calculate the entropy of vaporization of acetone at 296 K with an external pressure of 1 bar. The molar heat capacity of liquid acetone is 127 J/K-mol, its boiling point is 329.4 K, and its enthalpy of vaporization is 29.1 kJ/mol.
Step 1: change in entropy= C ln(T2/T1)= 127 * ln (329.4/296)= +13.5 J/K-mol
Step 2: change in entropy of vapor= 29.1/329.4= 88.3 J/K-mol
Step 3: change in entropy= 33.26 * ln (296/329.4)= -3.54