Chemistry WCH01: Acid-base Equilibria Topical Past Paper Questions

Propanoic acid is a weak acid with $ K_{a} = 1.30 \times 10^{-5} $ mol dm $ ^{-3} $. (a) (i) Write the expression for the acid dissociation constant, $ K_{a} $, of propanoic acid. (1) (ii) Calculate the pH of a solution of propanoic acid with a concentration of 0.120 mol dm $ ^{-…

This is a question about weak acids. (a) Calculate the pH of a 0.0500 mol dm $ ^{-3} $ solution of propanoic acid given that $ K_{a} = 1.34 \times 10^{-5} $ mol dm $ ^{-3} $ at 25°C. Give your answer to two decimal places. $$ \mathrm{CH_{3}CH_{2}COOH\rightleftharpoons CH_{3}CH_{2…

What is the pH of the following solutions? Use $ K_w = 1.00 \times 10^{-14} \, \text{mol}^2 \, \text{dm}^{-6} $ where necessary (a) 0.2 mol dm $ ^{-3} $ nitric acid. (1) ☐ A -0.7 ☐ B -0.2 ☐ C +0.2 ☐ D +0.7 (b) 0.200 mol dm $ ^{-3} $ barium hydroxide, Ba(OH) $ _2 $. (1) ☐ A 14.7 ☐…