Passing an electric current through a sample of water (H2O) can cause the water to decompose into hydrogen gas (H2) and oxygen g
as (O2) according to the following equation.. . 2H2O= 2H2 + O2 . . The molar mass of H2O is 18.01 g/mol. The molar mass of O2 is 32.00 g/mol. What mass of H2O, in grams, must react to produce 50.00 g of O2?. 14.07. 23.05. 28.14. 56.28
<span>2H2O= 2H2 + O2 </span> We are given the amount of oxygen to be produced in the reaction. The starting point for the calculations will be this amount.
50 g ( 1 mol O2 / 32 g O2 ) ( 2 mol H2O / 1 mol O2 ) ( 18.01 g H2O / 1 mol H2O) = 56.28 g of H2O is needed.