Question

Calculate the pH of the solution if the hydrogen ion concentration of the solution is 0.0001M.

• A. Red colour
• B. Blue-green colour
• C. Purple colour
• D. Orange colour

Answer 1

The correct option is B Blue-green colour

$pH=–log10\left[H^{+}\right]$
$pH=–log10\left(0.0001\right)$
$pH=–log10\left({10}^{-4}\right)$
$=–(–4){log}_{10}10[log10=1]$
$pH=4$