Determine the mass of 20 liters of chlorine.

We calculate the amount of chlorine equal to 20 liters:

n (Cl2) = V (Cl2): Vm = 20: 22.4 = 0.89 mol, (here V is the volume of chlorine, Vm is the molar volume of any gas, a constant value always equal to 22.4 l / mol).

Let’s calculate the molar mass of chlorine (it is numerically equal to the relative molecular mass, calculated in the same way):

M (Cl2) = 35.5 × 2 = 71 g / mol.

We find the mass of chlorine:

m (Cl2) = n (Cl2) × M (Cl2) = 0.89 × 71 = 63.4 (d).