Calculate the mass of iron oxide 3 that is required to obtain iron weighing 1 kg.

Let’s find the amount of iron substance by the formula:

n = m: M.

M (Fe) = 56 g / mol.

n = 1000 g: 56 g / mol = 17.86 mol.

Let’s find the quantitative ratios of substances.

Fe2O3 = 2Fe

For 1 mole of iron oxide, there are 2 moles of iron.

The substances are in quantitative ratios of 1: 2.

The amount of iron oxide substance will be 2 times less than the amount of iron substance.

n (Fe2O3) = ½ n (Fe) = 17.86: 2 = 8.93 mol.

Find the mass of iron oxide.

m = n × M.

M (Fe2O3) = 160 g / mol.

m = 160 g / mol × 8.93 mol = 1428.8 g.

Answer: 1428.8 g.