What mass of #"Fe"# is in #"316.80 g Fe"_2"O"_3"#?

1 Answer
Nov 10, 2015

Answer:

#"316.80 g Fe"_2"O"_3# contains #"221.56 g Fe"#.

Explanation:

One mole #"Fe"_2"O"_3"# contains two moles #"Fe"# atoms.

The molar mass of iron is 55.845 g/mol. Two moles of iron atoms equals #2xx55.845"g/mol Fe"="111.69 g/mol Fe"#.

Determine the percentage of iron in one mole of iron(III) oxide, which has a molar mass of #"159.70 g/mol"#.

#(111.69cancel"g/mol Fe")/(159.70cancel"g/mol Fe"_2"O"_3)xx100="69.937% Fe"#

In order to determine the grams of iron in 316.80 g of iron(III) oxide, multiply the percentage of #"Fe"# times #316.80"g Fe"_2"O"_3"#.

#0.69937 "Fe"xx316.80"g Fe"_2"O"_3="221.56 g Fe"#