Question

pH of 10^-15 M HCl solution is ______.

Options

• 7

• 6.8

• 7.2

• 6.5

Answer 1

pH of 10^-15 M HCl solution is 7.

Explanation:

\[\ce{10^-15 M HCl -> H+ + Cl-}\]

Total [H⁺] = [H⁺]_Acid + [H⁺]_water

= 10^-7 > 10^-15

[H⁺] ≈ 10^-7

pH = 7