Question

What is the pH of 0.01 M solution of ammonium hydroxide which is 10% dissociated?

Options

• 3.00

• 8.00

• 10.00

• 11.00

Answer 1

11.00

Explanation:

c = 10⁻² M

For a monoacid weak base,

[OH⁻] = c × α

[OH⁻] = `10^-2 xx 10/100`

[OH⁻] = 1 × 10⁻³ M

pOH = −log₁₀ [OH⁻]

= −log₁₀ (1 × 10⁻³)

pOH = 3.00

pH + pOH = 14

∴ pH = 14 − pOH

= 14 − 3.00

pH = 11.00