What mass of zinc must be dissolved in hydrochloric acid so that 5.6 g of iron (lll)

What mass of zinc must be dissolved in hydrochloric acid so that 5.6 g of iron (lll) can be obtained with the obtained hydrogen?

1. Let’s write down the reaction equations:

Zn + 2HCl = ZnCl2 + H2.

Fe2O3 + 3H2 = 2Fe + 3H2O.

2. Let’s write down the scheme of chemical reactions:

1.5Zn = Fe.

3. Find the amount of iron:

n (Fe) = m (Fe) / M (Fe) = 5.6 g / 56 g / mol = 0.1 mol.

4. According to the scheme, we find the amount, and then the mass of zinc:

n (Zn) = 2 / 3n (Fe) = 2/3 * 0.1 mol = 0.067 mol.

m (Zn) = n (Zn) * M (Zn) = 0.067 mol * 65 g / mol = 4.33 g.

Answer: m (Zn) = 4.33 g.