What do the coefficients in the following balanced chemical equation mean? 2h2 + o2 → 2h2o a) 2 moles of oxygen and 1 mole of hydrogen in the products b) 2 moles of hydrogen and 1 mole of oxygen in the products c) 2 moles of oxygen and 1 mole of hydrogen in the reactants d) 2 moles of hydrogen and 1 mole of oxygen in the reactants