The volume of hydrogen released by the action of an excess of hydrochloric acid on 21.6 g

The volume of hydrogen released by the action of an excess of hydrochloric acid on 21.6 g of aluminum is 21.5 liters. Find the yield fraction of the reaction product.

Aluminum reacts violently with hydrochloric acid. In this case, an aluminum chloride salt is formed and elemental hydrogen is released. The interaction is described by the following chemical equation.

Al + 3HCl = AlCl3 + 3/2 H2;

Let’s calculate the chemical amount of the evolved hydrogen gas.

To do this, we find the ratio of its volume to the volume of 1 mole of gas (filling a space with a volume of 22.4 liters).

N H2 = 21.5 / 22.4 = 0.96 mol;

To obtain such an amount of hydrogen, it is necessary to dissolve 0.96 x 2/3 = 0.64 mol of aluminum.

Let’s calculate its weight.

M Al = 27 grams / mol;

m Al = 27 x 0.64 = 17.3 grams;

The reaction yield is:

K = 17.3 / 21.6 = 0.8 = 80%;