Question

The pH of a solution of hydrochloric acid is 1.5. Calculate the concentration of the acid.

Options

• 2.5 × 10^–2 mol dm^–3

• 0.28 mol dm^–3

• 3.2 × 10^–2 mol dm^–3

• 0.0032 mol dm^–3

Answer 1

3.2 × 10^–2 mol dm^–3 

Explanation:

pH = – log [H]⁺

1.5 = – log [H⁺]

[H⁺] = antilog 1.5 = 0.032

= 3.2 × 10^–2 mol dm^–3