For ethanol, ΔvapH° = 43.5 kJ mol-1.
(i) Calculate q, w, ΔH and ΔU when 1.75 mol C2H5OH (l) is vaporised at 260 K at constant external pressure.
(ii) Explain whether the vaporisation of ethanol is exothermic or endothermic.
(iii) If methanol has a ΔvapH° = 37.4 kJ mol-1, would you expect methanol or ethanol to have greater intermolecular forces? Give a reason for your answer.