Calculate the mass and amount of phosphorus substance required for the reaction with 56 liters of oxygen.

Let’s write the equation of a chemical reaction.

4P + 5O2 = 2P2O5.

First, let’s determine the amount of oxygen.

n = V / Vm.

n = 56 / 22.4 = 2.5 mol.

Next, we determine the amount of phosphorus substance by the reaction equation.

X mol of phosphorus – 2.5 mol of oxygen

4 mol of phosphorus – 5 mol of oxygen.

X = 4 * 2.5 / 5 = 2 mol of phosphorus.

Next, we determine the mass of phosphorus.

n = m / M.

Let’s determine the molar mass of phosphorus.

M (P) = 31 g / mol.

m = 31 * 2 = 62 g.

The mass of phosphorus is 62 g.

Answer: the amount of phosphorus substance is 2 mol, the mass is 62 g.