A mixture contains Al2O3 (s) [MW=101.96 g/mol] and Fe2O3 (s) [MW=159.69 g/mol] and weighs 1.983g. when heated under excess hydrogen gas, the iron oxide reacts to form water vapor and Fe(s) but the aluminum oxide remains unreacted. If the residue following heating weighs 1.596g, determine the weight percent of iron oxide in the original mixture.