1. Explain Hess's law in your own words? (10 points) 2. Given the following two reactions and enthalpy data (10 points): N204(g) 2NO2(g) AH = +57.9 kJ 2NO(g) + O2(g) 2NO2(g) AH = 113.1 kJ Calculate the enthalpy change for the reaction in which 2NO(g) +O2(g) N204(g) DH = ?? kJ/mol =