4.8 g of magnesium was treated with excess hydrochloric acid. How much hydrogen will be released in this case?

The mass of magnesium is 4.8 g.

Let us determine how much hydrogen will be released as a result of this reaction.

First, you need to write down the reaction equations for this problem.

Mg + 2HCl = MgCl2 + H2.

First, you need to determine the amount of magnesium substance. To solve, you need to use the following formula:

n = m / M.

Let’s determine the molar mass of magnesium.

M (Mg) = 24 g / mol.

n (Mg) = 4.8 / 24 = 0.2 mol.

Next, we will determine the amount of hydrogen according to the reaction equation.

0.2 mol Mg – x mol H2.

1 mol Mg – 1 mol H2.

X = 1 * 0.2: 1 = 0.2 mol.

Answer: n (H2) = 0.2 mol.