Basically, I need confirmation on the heat produced when four mole of H2O is produced from Hydrogen and oxygen gas. I'm getting something ridiculous, basically saying that the temperature goes up to ~4000 degrees C. What I'm doing is using Hess's law to find the energies of reaction. H2 and O2 gas result in 0 KJ/mol. H2O is -285.8 KJ/mol. 4 mols x 285.8 KJ/mol = 1143.2 KJ I'm taking this and plugging it into the equation q=mC<>T (change in Temperature) so, 1143.2 = (18 g/mol H2O * 4 mol H2O = 72 g) * 4.18 j/(g*c) * <>T <>T = 3797 degrees C I know that when water forms from oxygen and hydrogen, the result is explosive, but thousands degrees C seems way too high. However...my logic seems right. Thoughts?