Calculate the mass of zinc that is needed to obtain 5.6 liters of hydrogen from a hydrochloric acid solution.

Zinc metal is converted to zinc chloride salt. The reaction is described by the following chemical reaction equation:

Zn + 2HCl = ZnCl2 + H2;

Let’s calculate the chemical amount of hydrogen. To do this, we divide the volume of gas by the volume of 1 mole of gas (which is 22.4 liters).

N H2 = 5.6 / 22.4 = 0.25 mol;

To obtain such an amount of hydrogen, it is necessary to dissolve 0.25 mol of zinc.

Let’s find the weight of zinc. To do this, we multiply the amount of substance by the weight of 1 mole of metal.

m Zn = 0.25 x 65 = 16.25 grams;