Answer
pH = 2.125
- Hydroxide ion concentration = $1.333 \times 10^{-12}M$
Work Step by Step
- HCl is a strong acid, therefore:
$[H_3O^+] = [HCl] = 0.0075M$
1. Calculate the pH Value
$pH = -log[H_3O^+]$
$pH = -log( 7.5 \times 10^{- 3})$
$pH = 2.125$
2. Calculate the $[OH^-]$:
$[H_3O^+] * [OH^-] = Kw = 10^{-14}$
$ 7.5 \times 10^{- 3} * [OH^-] = 10^{-14}$
$[OH^-] = \frac{10^{-14}}{ 7.5 \times 10^{- 3}}$
$[OH^-] = 1.333 \times 10^{- 12}M$
