Iron weighing 112 g burns completely in oxygen. Determine how much oxygen is required for this.

Iron combustion reaction in oxygen atmosphere:
4Fe + 3O2 = 2Fe2O3.
1) According to the periodic table, we determine the molar mass of iron: 56.
2) Find the amount of iron substance. For this, the mass of iron is divided by its molar mass: 112/56 = 2 mol.
3) According to the reaction equation, there are three moles of oxygen for four moles of iron. This means that the amount of oxygen substance is: 4 * 2/3 = 2.7 mol.
4) Find the volume of oxygen. For this, the amount of oxygen is multiplied by the molar volume: 2.7 * 22.4 = 60.48 liters – the answer.