1. The problem statement, all variables and given/known data The normal boiling point of hexane is 69.0°C. Estimate (a) its enthalpy of vaporization 3. The attempt at a solution In order to solve for ΔHvap in the Clausius-Clapeyron equation I need a reference T and p point. I extracted it from the triple point (T=178K and p=1,23Pa). I solve and I get 34kJ/mol, while the answer is 29,1kJ/mol. What i've done wrong? Thanks!