Using the Hess Law and the thermochemical equations below, MgO(s) + + 2HCl(aq) > MgCl2(g) + H2O(l) ΔHrxn = -111.7 kJ/mol

Mg(s) + 2 HCl(aq) > MgCl2(g) + H2(g) ΔHrxn = -548.3 kJ/mol

H2(g) + 1/2 O2(g) > H2O(l) ΔHrxn = -142.9 kJ/mol

find the heat of reaction of the following: (0.25 pt.)

Mg(s) + 1/2 O2(g) > MgO(g) ΔHrxn = ?

If the theoretical enthalpy of this reaction is -602 kJ/mol, calculate the percent error