20g of zinc containing 10% impurities reacted with hydrochloric acid. How much hydrogen will be released?

The mass of zinc is 20 g.

Mass fraction of impurities – 10%.

Let’s determine the volume of hydrogen that was formed.

First, let’s determine the mass of pure zinc.

100% – 10% = 90%.

20 * 0.9 = 18 g.

Zn + 2HCl = ZnCl2 + H2.

Let’s determine the amount of the substance and the molar mass of zinc.

M (Zn) = 65 g / mol.

n = m / M = 18/65 = 0.28 mol.

Using the reaction equation, we determine the amount of hydrogen substance.

0.28 mol of zinc – in a mol of hydrogen.

1 mol – 1 mol.

Y = 0.28 mol.

Let’s determine the volume of hydrogen.

V = n * Vm = 0.28 * 22.4 = 6.2 liters.

Answer: 6.2 liters.