What mass of iron will be obtained from iron oxide (lll), when it is reduced with 5.6 liters of hydrogen.

1. Let’s write down the reaction equation:

2Fe2O3 + 3H2 = 4Fe + 6H2O.

2. Find the amount of hydrogen (Vm – molar volume, constant equal to 22.4 l / mol):

n (H2) = V (H2) / Vm = 5.6 L / 22.4 L / mol = 0.25 mol.

3. According to the reaction equation, we find the amount and then the mass of the resulting iron:

4n (Fe) = 3n (H2).

n (Fe) = 0.75n (H2) = 0.75 * 0.25 mol = 0.1875 mol.

m (Fe) = n (Fe) * M (Fe) = 0.1875 mol * 56 g / mol = 10.5 g.

Answer: m (Fe) = 10.5 g.