5.6 liters of hydrogen sulfide was dissolved in 300 g of water. Determine the mass fraction

5.6 liters of hydrogen sulfide was dissolved in 300 g of water. Determine the mass fraction in percent of hydrogen sulfide in the resulting solution.

The mass fraction of hydrogen sulfide is determined by the expression:

w = m (H2S) / m (solution), where the mass of the solution is the sum of the mass of water and the mass of hydrogen sulfide.

Let’s find the mass of H2S. From the condition, we first determine the amount of substance:

n = 5.6 / 22.4 = 0.25 mol (since 1 mol of gas under normal conditions occupies a volume of 22.4 liters).

Hence m (H2S) = Mr * n = 34.1 * 0.25 = 8.5 g.

Then the mass fraction is:

w = 8.5 / (300 + 8.5) = 0.027. As a percentage, this value is 2.7%.