If this reaction releases 407 kJ of energy, how many grams of H2O are formed? Show the conversions required to solve this problem. 2H2(g)+O2(g)⟶2H2O(g)Δ𝐻=−484 kJ

Answer 1

2H₂(g) + O²(g) ⟶ 2H₂O(g) ... Δ𝐻 = −484 kJ

This tells us that 2 moles are H₂O are formed with the liberation of 484 kJ

407 kJ x 2 moles H₂O / 484 kJ = 1.68 moles H₂O

1.68 moles H₂O x 18 g / mol = 30.3 g H₂O formed