Calculate ΔHrxn for the following reaction:

Question

CaO(s)+CO2(g)→CaCO3(s)
Use the following reactions and given ΔH′s.
Ca(s)+CO2(g)+12O2(g)→CaCO3(s), ΔH= -812.8 kJ
2Ca(s)+O2(g)→2CaO(s), ΔH= -1269.8 kJ

Answer 1

dHrxn = (n*dHf products( - (n*dHf reactants)
Substitute and solve