When contaminated magnesium with a mass of 6 grams was dissolved in sulfuric acid, hydrogen

When contaminated magnesium with a mass of 6 grams was dissolved in sulfuric acid, hydrogen with a volume of 4.48 liters was obtained under normal conditions. determine the mass fraction of impurities.

Metallic magnesium dissolves in sulfuric acid solution. The chemical reaction proceeds according to the following equation:

Mg + H2SO4 = MgSO4 + H2 ↑;

Let’s calculate the chemical amount of a substance of metallic magnesium.

To do this, divide this weight by the weight of 1 mole of metallic magnesium.

M Mg = 24 grams / mol;

N Mg = 6/24 = 0.25 mol;

The same amount of hydrogen gas will be produced.

Let’s determine the volume of hydrogen.

To this end, we multiply the amount of substance by the volume of 1 mole of gas (which is 22.4 liters).

V H2 = 0.25 x 22.4 = 5.6 liters;

The reaction yield will be 4.48 / 5.6 = 0.8 = 80%;