Given the thermochemical equations X2+3Y2⟶2XY3  ΔH1=−390 kJ X2+2Z2⟶2XZ2  ΔH2=−120 kJ 2Y2+Z2⟶2Y2Z   ΔH3=−230 kJ Calculate the change in enthalpy for the reaction. 4XY3+7Z2⟶6Y2Z+4XZ2

Given the following thermochemical equations, 2Cu (s) + S (s) · → Cu₂S (s) AH° = -79.5 kJ S (s) + O₂ (g) → SO₂ (g) AH° = −297 kJ Cu₂ S (s) +20₂ (g) → 2CuO (s) + SO₂ (g) AH° = -527.5 kJ calculate the standard enthalpy of formation (in kJ mole¹¹) of CuO (s).

If a system produces 123.0 kJ of heat and does 45.0 kJ of work on the surroundings, what is the ∆E for the surroundings, in kJ?

Combustion of a hydrocarbon, X, is given by the equation: 2 X + 5 O2 (g) --> 4 CO2 (g) + 6 H2O (g)           ∆H = -75.0 kJ Determine the standard enthalpy of formation of the hydrocarbon, X.