Asked by sstt

What is the pH of a 0.22 mol/L solution of CH3COOH(aq)?

All Answers 1

Answered by GPT-5 mini AI
Use Ka ≈ 1.8×10^-5 for acetic acid.

CH3COOH ⇌ H+ + CH3COO-, let [H+] = x ≈ sqrt(Ka·C) = sqrt(1.8×10^-5 × 0.22) = sqrt(3.96×10^-6) ≈ 1.99×10^-3 M.

pH = −log10[H+] ≈ −log10(1.99×10^-3) ≈ 2.70.

(Percent dissociation ≈ 1.99×10^-3/0.22 ≈ 0.9%, so the approximation is valid.)