Acids and Bases Practice Questions PDF

1. What is the de nition of a Brønsted-Lowry acid? a) A proton acceptor. b) A proton donor. c) An electron pair donor. d) An electron pair acceptor. Answer: b) A proton donor. 2. What is the de nition of a Brønsted-Lowry base? a) A proton acceptor. b) A proton donor. c) An electron pair donor. d)...

1. What is the de nition of a Brønsted-Lowry acid? a) A proton acceptor. b) A proton donor. c) An electron pair donor. d) An electron pair acceptor. Answer: b) A proton donor. 2. What is the de nition of a Brønsted-Lowry base? a) A proton acceptor. b) A proton donor. c) An electron pair donor. d) An electron pair acceptor. Answer: a) A proton acceptor. 3. What is the ionic product of water, Kw? a) Kw = [H⁺] + [OH⁻] b) Kw = [H⁺] / [OH⁻] c) Kw = [H⁺][OH⁻] d) Kw = [H₂O] Answer: c) Kw = [H⁺][OH⁻] 4. What is the value of Kw at 298 K (25°C)? a) 1.0 x 10⁻⁷ mol² dm⁻⁶ b) 1.0 x 10⁻¹⁴ mol² dm⁻⁶ c) 1.0 x 10⁷ mol² dm⁻⁶ d) 1.0 x 10¹⁴ mol² dm⁻⁶ Answer: b) 1.0 x 10⁻¹⁴ mol² dm⁻⁶ 5. What is the pH of a neutral solution at 298 K? a) 0 b) 1 c) 7 d) 14 Answer: c) 7 fi fi 6. What is the pH of a 0.01 mol dm⁻³ solution of HCl (a strong acid)? a) 1 b) 2 c) 3 d) 4 Answer: b) 2 7. What is the pH of a 0.1 mol dm⁻³ solution of NaOH (a strong base)? a) 1 b) 10 c) 13 d) 14 Answer: c) 13 8. What is the concentration of H⁺ ions in a solution with a pH of 3? a) 1 x 10⁻¹ mol dm⁻³ b) 1 x 10⁻² mol dm⁻³ c) 1 x 10⁻³ mol dm⁻³ d) 1 x 10⁻⁴ mol dm⁻³ Answer: c) 1 x 10⁻³ mol dm⁻³ 9. What is the concentration of OH⁻ ions in a solution with a pH of 10? a) 1 x 10⁻¹ mol dm⁻³ b) 1 x 10⁻² mol dm⁻³ c) 1 x 10⁻³ mol dm⁻³ d) 1 x 10⁻⁴ mol dm⁻³ Answer: d) 1 x 10⁻⁴ mol dm⁻³ 10. What is the pH of a solution made by diluting 10 cm³ of 0.1 mol dm⁻³ HCl to 100 cm³? a) 1 b) 2 c) 3 d) 4 Answer: b) 2 11. Which of the following is the correct formula for calculating pH? a) pH = log[H⁺] b) pH = -log[H⁺] c) pH = [H⁺] d) pH = 1 / [H⁺] Answer: b) pH = -log[H⁺] 12. What is the relationship between pH and pOH? a) pH + pOH = 7 b) pH + pOH = 10 c) pH + pOH = 14 d) pH - pOH = 14 Answer: c) pH + pOH = 14 13. If the concentration of H+ ions doubles, what is the approximate change in pH? a) Increases by 0.3 b) Decreases by 0.3 c) Doubles d) Halves Answer: b) Decreases by 0.3 14. What is the [H⁺] of a solution that is 1.0 x 10⁻⁵ M in OH⁻ at 298K? a) 1.0 x 10⁻⁵ M b) 1.0 x 10⁻⁷ M c) 1.0 x 10⁻⁹ M d) 1.0 x 10⁻¹⁴ M Answer: c) 1.0 x 10⁻⁹ M 15. What is a conjugate acid-base pair? a) Two acids that react together. b) Two bases that react together. c) Two species that differ by one proton (H⁺). d) Two species with the same number of protons. Answer: c) Two species that differ by one proton (H⁺). 16. In the reaction: NH₃ + H₂O ⇌ NH₄⁺ + OH⁻, which species is the conjugate acid of NH₃? a) H₂O b) NH₄⁺ c) OH⁻ d) There is no conjugate acid. Answer: b) NH₄⁺ 17. Which of these is *not* a strong acid? a) HCl b) HNO₃ c) H₂SO₄ d) Ethanoic acid (CH₃COOH) Answer: d) Ethanoic acid (CH₃COOH) 18. How does increasing temperature effect the value of Kw? a) Kw Decreases with increasing temperature b) Kw increases with increasing temperature c) Kw remains constant d) No correlation can be made Answer: b) Kw increases with increasing temperature 19. What is the pH of 0.020 mol dm⁻³ sulfuric acid, H₂SO₄? a) 1.4 b)1.7 c) 2.0 d) 4 Answer: b) 1.7