Calculate the mass of zinc required for the reaction with an excess of hydrochloric acid solution

Calculate the mass of zinc required for the reaction with an excess of hydrochloric acid solution so that the evolved hydrogen reduces 4 g of copper oxide (2) to metallic copper?

When dissolved in hydrochloric acid, metallic zinc is converted to zinc chloride.

Zn + 2HCl = ZnCl2 + H2;

The reduction reaction of copper oxide is described by the following chemical reaction equation:

CuO + H2 = Cu + H2O;

Let’s determine the chemical amount of zinc oxide.

M CuO = 64 + 16 = 80 grams / mol;

N CuO = 4/80 = 0.05 mol;

To restore such an amount of oxide, it is necessary to take 0.05 mol of hydrogen, and for this it is necessary to dissolve 0.05 mol of zinc in acid.

Let’s calculate its weight.

m Zn = 0.05 x 65 = 3.25 grams;