1 Chemistry 12 Unit 4 Topic A Handin Assignment Answer the following multiplechoice and written response problems on your own paper. Submit your answers for marking. You do not need to show your work for the multiplechoice problems, but ALL work (when applicable) must be shown in your solutions to the written response problems. Ensure you put your name on your assignment and write Chemistry 12 Unit 4 Topic A on the top of it. Part A: MultipleChoice SelfTest: Select the letter of the best response, then mark your answers with the answer key provided. 1. A property that is exhibited by both acids and bases in solution is that they A. taste bitter. C. conduct electricity. B. react with Zn. D. turn red litmus blue. 2. An Arrhenius acid is a substance that A. accepts a proton. C. produces H + in solution. B. donates a proton. D. produces OH in solution. 3. The balanced formula equation for the neutralization of H 2 SO 4 by KOH is A. H 2 SO 4(aq) + KOH (aq) KSO 4(aq) + H 2 O (l) B. H 2 SO 4(aq) + KOH (aq) K 2 SO 4(aq) + H 2 O (l) C. H 2 SO 4(aq) + 2KOH (aq) K 2 SO 4(aq) + H 2 O (l) D. H 2 SO 4(aq) + 2KOH (aq) K 2 SO 4(aq) + 2H 2 O (l) 4. Caustic soda, NaOH, is found in A. fertilizers. C. toothpaste. B. beverages. D. oven cleaners. 5. The hydronium ion, H 3 O +, is a water molecule that has A. lost a proton. C. gained a neutron. B. gained a proton. D. gained an electron.
2 6. Which one of the following defines BrønstedLowry acids and bases? A. acids accept H + ; bases donate H + B. acids donate H + ; bases accept H + C. acids accept H + ; bases donate OH D. acids contain H + ; bases contain OH 7. Which conjugate acidbase pair has the base written first? A. HPO 2 3 4 / PO 4 B. H 2 PO 2 4 / HPO 4 C. HPO 2 4 / H 2 PO 4 D. H 3 PO 4 / H 2 PO 4 8. Consider the following acidbase reaction: HSO 3 (aq) + HF (aq) H 2 SO 3(aq) + F (aq) The correct order for BrønstedLowry acids and bases is A. acid + base acid + base. B. acid + base base + acid. C. base + acid base + acid. D. base + acid acid + base. 9. Which one(s) of the following substance is/are amphiprotic? 1. H 3 PO 4 2. H 2 PO 4 3. HPO 4 2 A. 2 only C. 1 and 2 B. 3 only D. 2 and 3 10. Water acts as a BrønstedLowry base in which of the following equilibria: A. III only. C. II and III only. B. I and II only. D. I, II and III. I HCO 3 (aq) + H 2 O (l) H 2 CO 3(aq) + OH (aq) II NH 4 + (aq) + H 2 O (l) H 3 O + (aq) + NH 3(aq) III HSO 3 (aq) + H 3 O + (aq) H 2 O (l) + H 2 SO 3(aq)
3 11. The conjugate acid of PO 4 3 is A. H 3 O + C. H 3 PO 4 2 B. HPO 4 D. H 2 PO 4 12. Using the following equilibrium system, identify a conjugate BrønstedLowry acid and base pair: A. HSO 4 (acid) and HPO 4 2 (base) B. HPO 4 2 (acid) and HSO 4 (base) C. H 2 PO 4 (acid) and HPO 4 2 (base) D. H 2 SO 4 (acid) and H 2 PO 4 (base) H 2 SO 4(aq) + HPO 4 2 (aq) H 2 PO 4 (aq) + HSO 4 (aq) 13. The conjugate acid of H 2 C 6 H 5 O 7 is A. C 6 H 5 O 3 7. C. H 2 C 6 H 5 O 7. B. HC 6 H 5 O 7. D. H 3 C 6 H 5 O 7. 14. Which of the following solutions will have the greatest electrical conductivity? A. 1.0 M HCl C. 1.0 M H 3 BO 3 B. 1.0 M HNO 2 D. 1.0 M HCOOH 15. The strength of an acid depends upon its A. concentration. C. K b value. B. degree of ionization. D. electrical conductivity. 16. How many acids from the list below are known to be weak acids? A. 2 C. 4 B. 3 D. 5 HCl, HF, H 2 SO 3, HNO 3, HNO 2
4 17. In the following BrønstedLowry acidbase equation: The stronger base is A. NH + 4. C. NH 3. B. H 2 O. D. H 3 O +. NH 4 + (aq) + H 2 O (l) NH 3(aq) + H 3 O + (aq) 18. Which of the following acids will have the greatest [OH ]? A. 1.0 M HI C. 1.0 M HCN B. 1.0 M HF D. 1.0 M H 2 SO 4 19. Which of the following is the strongest acid in water? A. H 3 O + C. HClO 4 B. H 2 O D. H 2 SO 4 20. Water will act as a BrønstedLowry acid with A. NH 3 C. HCN B. H 2 S D. HNO 3 21. Water acts as a base when it reacts with A. CN. C. NO 2. B. NH 3. D. NH + 4. 22. Consider this equilibrium: At equilibrium, HCO 3 (aq) + H 2 C 6 H 5 O 7 (aq) H 2 CO 3(aq) + HC 6 H 5 O 7 2 (aq) A. products are favoured and H 2 CO 3 is the stronger acid. B. reactants are favoured and H 2 CO 3 is the stronger acid. C. products are favoured and H 2 C 6 H 5 O 7 is the stronger acid. D. reactants are favoured and H 2 C 6 H 5 O 7 is the stronger acid.
5 23. Which statement correctly describes the [H 3 O + ] in 0.10 M solutions of H 3 BO 3 and H 2 S? A. The [H 3 O + ] is less in H 3 BO 3 since H 3 BO 3 is a stronger acid than H 2 S. B. The [H 3 O + ] is less in H 3 BO 3 since H 3 BO 3 is a weaker acid than H 2 S. C. The [H 3 O + ] is greater in H 2 S since H 3 BO 3 is a stronger acid than H 2 S. D. The [H 3 O + ] is equal in both solutions H 3 BO 3 and H 2 S are both weak acids. 24. Which of the following is the strongest base that can exist in an aqueous solution? A. NH 3 C. HF B. NaNH 2 D. OH 25. The net ionic equation for the hydrolysis reaction occurring in a solution of NaF is: A. F (aq) + H 2 O (l) HF (aq) + OH (aq) B. NaF (aq) + H 2 O (l) NaOH (aq) + HF (aq) C. NaF (aq) + 2H 2 O (l) H 3 O + (aq) + OH (aq) + Na + (aq) + F (aq) + D. Na(H 2 O) 6 (aq) + H 2 O (l) H 3 O + (aq) + Na(H 2 O) 5 OH (aq) 26. Which of the following solutions is acidic? A. KOH (aq) C. Na 2 CO 3(aq) B. NH 4 Cl (aq) D. NaCH 3 COO (aq) End of Part A Answers to Part A: 1. C 2. C 3. D 4. D 5. B 6. B 7. C 8. D 9. D 10. C 11. B 12. C 13. D 14. A 15. B 16. B 17. C 18. C 19. A 20. A 21. D 22. C 23. B 24. D 25. A 26. B Part B Starts on the Following Page
6 Part B: Written Response Problems. Show all work!! Marks as indicated. 19 marks total. 1. Use the Arrhenius Theory to classify the following compounds as Acids, Bases or Salts. (0.5 marks each, 3 marks total) a) HCl d) H 3 PO 3 b) NaF e) Fe 2 O 3 c) Sr(OH) 2 f) Mg(OH) 2 2. Use the BrønstedLowry Theory to write ionization equations that show following acids ionizing in water. (1 mark each, 2 marks total) (THINK: Are they strong or weak? What difference does that make in their ionization equations?) a) HNO 3 b) H 2 CO 3 3. Write equations to show how the following bases react with water according to the BrønstedLowry definition of a base. (1 mark each, 2 marks total) a) HS b) S 2 4. The reactants are favoured in the equilibrium: H 2 Se (aq) + HTe (aq) HSe (aq) + H 2 Te (aq) a) Write the chemical formula of the stronger acid. (1 mark) b) Write the chemical formula of the weaker base. (1 mark) 5. The hydrogen sulphite ion, HSO 3, is amphiprotic. a) Write the equation for the reaction between HSO 3 (aq) and CO 3 2 (aq). (1 mark) b) Write the equation for the reaction between HSO 3 (aq) and HF (aq). (1 mark) THIS ASSIGNMENT CONTINUES ON THE NEXT PAGE!!
7 6. For each of the following salts listed below: i) Write the chemical formulae of the ions it contains. (DO NOT WRITE A DISSOCIATION EQUATION) ii) State whether or not each ion hydrolyzes. iii) Write a hydrolysis equation for each ion that hydrolyzes. iv) State whether the solution will be acidic, basic or neutral. a) SrCl 2 b) NH 4 NO 3 c) LiF d) Al(HSO 4 ) 3 (8 marks total) End of Assignment