Determine the mass of zinc (Zn) reacted with a 30 gram hydrochloric acid solution. Omega is 20%.

The reaction of dissolving zinc in hydrochloric acid is described by the following chemical reaction equation:

Zn + 2HCl = ZnCl2 + H2;

When 1 mol of zinc is dissolved, 1 mol of hydrogen gas is released. This consumes 2 mol of acid.

Let’s calculate the chemical amount of a substance contained in 30 grams of 20% acid.

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

N HCl = 30 x 0.2 / 36.5 = 0.1644 mol;

This will dissolve 0.1644 / 2 = 0.0822 mol of zinc.

Let’s calculate its weight.

M Zn = 65 grams / mol;

m Zn = 65 x 0.0822 = 5.343 grams;