Question

What is the pH of a 0.222 M acetic acid solution?

A)13.35

B)2.70

C)11.3

D)0.65

Answer 1

pH=2.7

Further explanation

Acetic acid = weak acid

`\tt [H^+]=√(Ka.M)`

Ka = acid ionization constant

M = molarity

Ka for Acetic acid(CH₃COOH) : 1.8 x 10⁻⁵

`\tt [H^+]=\sqrt{1.8* 10^(-5)* 0.222}\\\\=0.001998=1.998* 10^(-3)`

`\tt pH=3-log~1.998=2.7`