To 200 grams of 15% sulfuric acid solution was added excess magnesium metal. Determine the volume of evolved hydrogen.

Magnesium dissolves in sulfuric acid solution. The reaction is described by the following chemical equation:

Mg + H2SO4 = MgSO4 + H2 ↑;

Let’s determine the molar amount of sulfuric acid.

To do this, divide its weight by the weight of 1 mole of acid.

M H2SO4 = 2 + 32 + 16 x 4 = 98 grams / mol;

N H2SO4 = 200 x 0.15 / 98 = 0.306 mol;

An equivalent amount of hydrogen will be obtained.

Let’s find the volume of hydrogen.

For this purpose, we multiply the amount of substance by the volume of 1 mole of gas (filling volume 22.4 liters).

V H2 = 0.306 x 22.4 = 6.86 liters;