Calculate the heat of formation of SiO4(s), given that the heats of formation of SiO2(s), -910.90 KJ/mol; H2O(l), -285.8 KJ/mol; HF (g), -271.1 KJ/mol.

Question

I know the heat of formation is products minus reactants but how do i do this when no reaction is given please help

Answer 1

-193.36