The molar enthalpy change of vaporizing ethanol is 38.6 kJ/mol at the boiling point (78.4 °C); likewise, at-33.34 °C it takes 23.35 kJ/mol for ammonia to boil. If you determine the ΔS for one mole of each of these substances, would you say that the values are very different from each other? Why might that be? The entropy of a liquid is much, much smaller than a gas, and you arebasically calculating Sgas-Sliq. Also, do perfect gases have very different entropies if P, T and V are the same.