The standard enthalpies of formation, Hf, for C2H2(g),O2(g),CO(g),H2O(g), and CO2(g) are given in the table. Use this information to calculate the overall heat of the reaction that converts 1 mole of C2H2(g) and a stoichiometric amount of O2(g) into CO(g) and H2O(g). Hint: Start by writing a balanced thermochemical equation for the reaction