What mass of a 15% hydrochloric acid solution is required to completely dissolve 12 g of magnesium?

Let’s write the reaction equation:

Mg + 2HCl → MgCl2 + H2 (magnesium chloride, hydrogen).

Let’s find the amount of magnesium substance:

n (Mg) = m (Mg) / M (Mg) = 12 g / 24 g / mol = 0.5 mol.

Based on the reaction equation, we find the amount of hydrochloric acid substance:

n (HCl) = 2 * n (Mg) = 2 * 0.5 mol = 1 mol.

We calculate the mass of hydrochloric acid:

m (HCl) = n (HCl) * M (HCl) = 1 mol * 36.5 g / mol = 36.5 g.

Let’s use the formula:

wr.v. = (mr.w. * 100%) / mr-ra

Let us express the mass of the solution:

mr-ra (HCl) = (mr.w. * 100%) / wr.w. = (36.5 g * 100%) / 15% = 243.33 g.

Answer: 243.33 g.