问题详情

It is difficult to prepare many compounds directly from the elements，so values for these compounds cannot be measured directIy. For many organic compounds，it is easier to measure the standard enthalpy of combustion by reaction of the compounds with excess O₂(g) to form CO₂(g) and H₂O(l). From the following standard enthalpies of combustion at 298.15K，determine for the compound．
(1)cyclohexane，C₆H₁₂(l)，a useful organic solvent：=-3920kJ·mol^-1
(2)phenol，C₆H₅OH(s)，used as a disinfectant and in the production of thermo-setting plastics：=-3053kJ·mol^-1