Determine the chemical amount and weight of the released hydrogen obtained by dissolving magnesium

Determine the chemical amount and weight of the released hydrogen obtained by dissolving magnesium in a solution of hydrochloric acid with a weight of 400 g (weight fraction of hydrochloric acid in the solution is 20%)

Magnesium interacts with hydrochloric acid. In this case, magnesium chloride is synthesized and hydrogen gas is released. This reaction is described by the following chemical reaction equation:

Mg + 2HCl = MgCl2 + H2;

In accordance with the coefficients of the equation, in the reaction of 2 mol of acid, 1 mol of hydrogen gas is released.

Let’s calculate the chemical amount of the acid. To do this, divide its weight by the weight of 1 mole of acid.

M HCl = 1 + 35.5 = 36.5 grams / mol;

N HCl = 400 x 0.2 / 36.5 = 2.192 mol;

During the reaction, half the amount of hydrogen will be synthesized.

N H2 = 2.192 / 2 = 1.096 mol;

Let’s calculate its weight, for this we multiply the amount of substance by the weight of 1 mole of gas:

m H2 = 1.096 x 2 = 2.192 liters;