what is the change of enthalpy change of the following reaction N2O (g) + NO2 (g) 3 NO (g)
NO (g) + ½ O2 (g) NO2 (g) DH = -56.6 kJ
N2O (g) N2 (g) + ½ O2 (g) DH = -81.6 kJ
½ N2 (g) + ½ O2 (g) NO (g) DH = +90.4 kJ