Calculate the volume of 68 g H2S hydrogen sulphide.

1) Find the amount of hydrogen sulfide contained in its 68 grams, using the formula:

amount of substance = mass of substance: molar mass of a substance.

Let’s substitute the data into this formula:

amount of hydrogen sulfide = 68 g: 34 = 2 (mol).

2) According to Avogadro’s law: “The same number of molecules of different gases, under the same conditions, occupies the same volume.”
That is, the volume of one mole of any gas is 22.4 liters (under normal conditions). Knowing this, we calculate the volume of 2 mol of hydrogen sulfide:

volume of hydrogen sulfide = 22.4 l * 2 = 44.8 (l).