As a result of burning iron in oxygen, 4.64 g of iron scale (Fe3O4) was formed. How much oxygen has reacted?

1) Calculate the amount of molar iron scale: M (Fe3O4) = 232 g / mol, n (Fe3O4) = 4.64 / 232 = 0.02 mol;
2) Determine the number of moles of oxygen: n (O2) = (1/2) * n (Fe3O4) = (1/2) * 0.02 = 0.01 mol;
3) Calculate the volume of reacted oxygen at normal conditions: Vm = 22.4 l / mol, V (O2) = 22.4 * 0.01 = 0.224 l;
Answer: 0.224 l