# How much hydrogen will be released if by 12g. magnesium add a solution containing 7.3 g of hydrochloric acid?

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

M Mg = 24 grams / mol;

N Mg = 12/24 = 0.5 mol;

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 = 7.3 / 36.5 = 0.2 mol;

Thus, we have an excess of metal and a lack of acid.

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

Let’s calculate its volume, for this we multiply the amount of substance by the volume of 1 mole of gas (22.4 liters):

V H2 = 0.2 / 2 x 22.4 = 2.24 liters;