Final answer:
To produce 12 moles of phosphorous acid from diphosphorus trioxide, 659.64 grams of P2O3 are required, based on the stoichiometric relationship provided by the balanced chemical equation.
Step-by-step explanation:
The question asks how many grams of diphosphorus trioxide, P2O3, are needed to produce 12 moles of phosphorous acid (H3PO3). According to the balanced chemical equation 3P2O3 + 6H2O → 6H3PO3, 3 moles of P2O3 produce 6 moles of phosphorous acid. Therefore, to produce 12 moles of H3PO3, we need 6 moles of P2O3. To find the mass in grams of those 6 moles of P2O3, we first determine the molar mass of P2O3 by adding twice the atomic mass of phosphorus (2 × 30.97 g/mol) to three times the atomic mass of oxygen (3 × 16.00 g/mol), which equals 109.94 g/mol. We then multiply the number of moles by the molar mass, 6 moles × 109.94 g/mol, to obtain the mass of P2O3 needed, which is 659.64 grams.