The following thermochemical equation is for the reaction of Fe 3 O 4 (s) with hydrogen (g) to form iron and water vapor Fe 3 O 4 (s)+4H 2 (g) 3Fe(s)+4H 2 O(g) When 64.6 grams of Fe 3 O 4 (s) react with excess hydrogenſe) how much heat is absorbed?