Question

Calculate the pH of a solution which is ${10}^{-1}MinHCland{10}^{-3}MinC{H}_{3}COOH[K_a=2\times {10}^{-3}]$

• A. 2
• B. 4
• C. 1
• D. 3

Answer 1

The correct option is C 1

$H^{+}$ ion can be considered completely from HCI due to less dissociation of $C{H}_{3}COOH$ (because of common ion effect by $H^{+}$ of HCI, $\alpha$ << 1) and its low conc. So, $\left[H^{+}\right]={10}^{-1}M$
$\therefore pH=1$