6.36 We need to calculate a standard-state H^r for the oxidation of p-xylene (C8H10) to terephthalic acid (TPA, C8O4H6), which is used in making plastic 2-L soda bottles. However, heats of formation of the compounds from the respective elements are not available. Reference tables do have information on heats for combustion to CO2(g) and H2O(l) at 25C, and show that the energy released is 1089kcal/mol for p-xylene (1) and 770 kcal/molforTPA(s). C8H10(l)+3O2(g)C8O4H6(s)+2H2O(l) Determine a numerical value for Hr. Given that H^f for CO2=94 kcal/mol and Hf for liquid H2O=68kcal/mol, calculate Hf for p-xylene and TPA