Under the action of hydrochloric acid on a mixture of zinc and zinc oxide weighing = 20 grams, 0.2 mol

| June 17, 2021 | education

Under the action of hydrochloric acid on a mixture of zinc and zinc oxide weighing = 20 grams, 0.2 mol of gas was released. find the mass fraction of the components of the mixture

Let’s compose the equations of the reactions taking place in the mixture.

Zn + 2HCl = ZnCl2 + H2 ↑.

ZnO + 2HCl = ZnCl2 + H2O.

Hydrogen is released as a result of the reaction between zinc and hydrochloric acid. According to the reaction equation, there is 1 mole of zinc for 1 mole of hydrogen. Substances are in quantitative ratios 1: 1. The amount of substances will be equal.

n (Zn) = n (H2) = 0.2 mol.

Let’s find the mass of zinc.

m = n × M.

M (Zn) = 65 g / mol.

m = 65 g / mol × 0.2 mol = 13 g.

Let’s find the mass fraction of zinc in the mixture.

13 g – x%,

20 g – 100%.

X = (13g × 100%): 20g = 65%.

Find the mass fraction of zinc oxide in the mixture.

100% – 65% = 35%.

Answer: 35%; 65%.



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