Find the heat of reaction h for each of the following

Question

Find the heat of reaction (ΔH) for each of the following chemical reactions and note whether each reaction is exothermic or endothermic.

1. SiO2 (s) + C(s)  CO2 (g) + Si(s)  where ΔHf for SiO2 (s) = -861 kJ/mol
2. P4O10 (s) + 6 H2O(l)  4 H3PO4 (s)   where ΔHf for P4O10 (s) = -3024 kJ/mol and ΔHf for H3PO4 (s) = -1273 kJ/mol