The mass of oxygen required to burn 67.2 liters of hydrogen sulfide to S02 is …

1. Let’s write down the reaction equation:

2H2S + 3O2 = 2SO2 ↑ + 2H2O.

2. Let’s convert the volume of hydrogen sulphide to the amount (Vm is a constant equal to 22.4 mol / l):

n (H2S) = V (H2S) / Vm = 67.2 L / 22.4 L / mol = 3 mol.

3. Using the equation, we find the amount of oxygen, and then its mass:

3n (O2) = 2n (H2S)

n (O2) = 2n (H2S) / 3 = (2 * 3 mol) / 3 = 2 mol.

m (O2) = n (O2) * M (O2) = 2 mol * 32 g / mol = 64 g.

Answer: 64 g.