Consider the reaction: A2 + B2 → 2AB, with standard enthalpy of formation ΔHf0 = -200 kJ/mol. Here AB, A2, and B2 are diatomic molecules. If the bond enthalpies of A2, B2, and AB are in the ratio 1 : 0.5 : 1, then the bond enthalpy of A2 is _________ kJ/mol.

A bomb calorimeter measures:

Given the following thermochemical equations: 2Cu2O(s) + O2(g) → 4CuO(s) ΔH° = -287.9 kJ Cu2O(s) → CuO(s) + Cu(s) ΔH° = 11.3 kJ What is the standard heat of formation of CuO(s)?

Given the reactions: CH4(g) + 2O2(g) → CH2O(g) + H2O(g), ΔH° = -326.9 kJ CH2O(g) + O2(g) → CO2(g) + H2O(g), ΔH° = -563.5 kJ What is ΔH° for the overall reaction: CH4(g) + 3O2(g) → CO2(g) + 2H2O(g)?