page 06 9. What is the concentration of hydroxide ions, in mol l-1, in a solution with a pH of 8·5? A 8·5 × 10-6 B 3·2 × 10-6 C 8·5 × 10-9 D 3·2 × 10-9 10. Butanoic acid is a weak acid which dissociates as shown. C3H7COOH(aq) + H2O(ℓ) Ý C3H7COO-(aq) + H3O+(aq) The equilibrium position can be shifted to the right by the addition of A a catalyst B sulfuric acid C sodium hydroxide D sodium butanoate. 11. Which of the following salts forms an alkaline solution in water? A Sodium sulfate B Lithium chloride C Ammonium nitrate D Potassium propanoate 12. Which of the following combinations would produce a buffer solution? A Sodium chloride and ammonia B Ammonium chloride and ammonia C Sodium chloride and sodium hydroxide D Ammonium chloride and sodium hydroxide