Name Class Date. In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question.

Transcription

1 Assessment Chapter Test A Chapter: Acids and Bases In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1. Which of the properties listed below is not characteristic of an acid? a. a sour taste b. a slippery feel c. the ability to conduct an electric current d. reactivity with metals 2. Which is an example of a weak acid? a. HCl b. H 2 SO 4 c. H 3 PO 4 d. HNO 3 3. Acetic acid is found in a. vinegar. b. the stomach. c. antacids. d. oranges. 4. A characteristic of an Arrhenius base is that it a. is an electrolyte. b. tastes bitter. c. dissociates to form OH ions. d. All of the above 5. Which of the following is a Brønsted-Lowry base? a. HCl b. HCO 3 c. H 3 O d. H 3 PO 4 6. In the reaction represented by the equation H 2 C 2 O 4 (aq) CH 3 NH 2 (aq) HC 2 O 4 (aq) CH 3 NH 3 (aq), which of these is a conjugate acid-base pair? a. H 2 C 2 O 4 (aq) and CH 3 NH 2 (aq) b. H 2 C 2 O 4 (aq) and CH 3 NH 3 (aq) c. CH 3 NH 2 (aq) and CH 3 NH 3 (aq) d. HC 2 O 4 (aq) and CH 3 NH 3 (aq) Modern Chemistry 125 Chapter Test

2 Chapter Test A, continued 7. What is the correct formula for hydrosulfuric acid? a. H 2 SO 4 b. H 2 S c. H 2 SO 3 d. SO What is the correct acid name for an aqueous solution of HClO 4? a. hypochlorous acid b. chlorous acid c. chloric acid d. perchloric acid 9. A substance that increases the concentration of OH ions in an aqueous solution is known as a(n) a. Arrhenius acid. b. Arrhenius base. c. Lewis acid. d. Lewis base. 10. An Arrhenius acid in an aqueous solution a. attracts negatively charged anions. b. attracts positively charged cations. c. gives up one or more of its hydrogen ions to water molecules. d. forms ionic bonds with water molecules. 11. Which of the following is an indication of acid strength? a. the number of hydrogen atoms in the formula of the acid b. how strongly an aqueous solution of the acid conducts an electric current c. how quickly the acid dissolves in water d. the number of total atoms in one molecule of the acid 12. Which of the following is an organic acid? a. CH 3 COOH b. H 2 SO 4 c. HI d. HClO The neutralization of any strong acid and strong base produces mostly a. H 2 O molecules. b. H 3 O and OH ions. c. H 3 O ions. d. OH ions. Modern Chemistry 126 Chapter Test

3 Chapter Test A, continued 14. A strong base in an aqueous solution a. is a weak electrolyte. b. produces many H ions. c. will not dissolve. d. completely dissociates into ions. 15. In a Brønsted-Lowry acid-base reaction, what are transferred from one reactant to another? a. electrons b. water molecules c. protons d. OH ions 16. How many protons per molecule can a monoprotic acid donate? a. one b. two c. three d. zero 17. How many stages of ionization does phosphoric acid go through? a. one b. two c. three d. four 18. Which substance is a Lewis acid in the reaction shown by the equation below? BF 3 (aq) F (aq) BF 4 (aq) a. BF 3 b. F c. BF 4 d. None of the above 19. What is the conjugate acid of water? a. OH b. H 3 O c. H 2 O 2 d. HOH 20. HCl is a strong acid. When it combines with water, the conjugate of HCl will be a a. weak base. b. weak acid. c. strong base. d. strong acid. Modern Chemistry 127 Chapter Test

4 Chapter Test A, continued 21. Which is the stronger base in the reaction represented by the following equation? CH 3 COOH(aq) H 2 O(l) H 3 O (aq) CH 3 COO (aq) a. CH 3 COOH b. CH 3 COO c. H 3 O d. H 2 O 22. Consider the reaction represented by the equation below. HClO 4 (aq) H 2 O(l) H 3 O (aq) ClO 4 (aq) Which substances are present in the greatest concentrations? a. HClO 4 and H 2 O b. HClO 4 and ClO 4 c. H 3 O and ClO 4 d. H 2 O and H 3 O 23. Consider the two equations below. H 2 SO 4 (aq) H 2 O(l) H 3 O (aq) HSO 4 (aq) NH 3 (g) H 2 O(l) NH 4 (aq) OH (aq) They illustrate that water is a. an acid in both reactions. b. a base in both reactions. c. amphoteric. d. a weak electrolyte. 24. What is the correct net ionic equation for the neutralization reaction between the substances below? HNO 3 (aq) KOH(aq) a. NO 3 (aq) K (aq) KNO 3 (aq) b. H 3 O (aq) OH (aq) 2H 2 O(l) c. H 3 O (aq) NO 3 (aq) K (aq) OH (aq) NO 3 (aq) K (aq) 2H 2 O(l) d. HNO 3 (aq) KOH(aq) KNO 3 (aq) H 2 O(l) 25. Sulfur trioxide gas dissolves in atmospheric water. The product of the reaction, which falls to the ground as a component of acid rain or snow, is a. H 2 SO 4 (aq). b. H 2 S(aq). c. H 3 O (aq). d. SO 2 4 (aq). Modern Chemistry 128 Chapter Test

5 TEACHER RESOURCE PAGE dissolves. The ions, already present, separate from one another. Ionization is the process of forming ions from the solute molecules by the action of the solvent. When a molecular compound dissolves and ionizes in a polar solvent, ions are formed. 21. In a strong electrolyte, all or almost all of the dissolved compound exists as ions in aqueous solution. In a weak electrolyte, little of the dissolved compound exists as ions in aqueous solution. 22. When a compound containing hydrogen dissolves in water to form a hydrogen ion, H, the H ion attracts other molecules or ions so strongly that it rarely exists alone. In water, the H ion immediately bonds to a water molecule, forming a hydronium ion, H 3 O. 23. Dissolved salt will lower the freezing point of water. Therefore, adding salt to icy roads will help melt the ice and prevent further freezing of any water on the road s surface. It will also prevent the refreezing of water as it melts. 24. none 25. Ba 2 (aq) SO 4 2 (aq) BaSO 4 (s) 26. Cd 2 (aq) S 2 (aq) CdS(s) 27. none 28. none g/mol C/m C C/m g C 14 Acids and Bases, pp TEST A 1. b 2. c 3. a 4. d 5. b 6. c 7. b 8. d 9. b 10. c 11. b 12. a 13. a 14. d 15. c 16. a 17. c 18. a 19. b 20. a 21. d 22. c 23. c 24. b 25. a TEST B 1. d 2. d 3. c 4. c 5. a 6. b 7. a 8. b 9. strong 10. binary 11. conjugate base 12. diprotic 13. acids, water, salt 14. amphoteric 15. carbon dioxide, barium chloride, water 16. nitrous acid 17. hydrochloric acid 18. carbonic acid 19. sulfuric acid 20. hydriodic acid 21. hypobromous acid 22. H 2 S 23. HNO H 3 PO HClO HCl and Cl NH 3 and NH acidic: HCl and NH 4 basic: NH 3 and Cl 28. H 2 O and OH NH 3 and NH proton donors: H 2 O and NH 4 proton acceptors: OH and NH HCl(aq) NaOH(aq) NaCl(aq) H 2 O(l) 31. H 3 O (aq) Cl (aq) Na (aq) OH (aq) Na (aq) Cl (aq) 2H 2 O(l) 32. H 3 O (aq) OH (aq) 2H 2 O(l) 33. HIO 3, HIO, HIO HIO, HIO 3, HIO A strong acid ionizes completely in an aqueous solution. A weak acid does not ionize completely in aqueous solution. Its aqueous solution contains hydronium ions, anions, and dissolved acid molecules. 36. Sulfur trioxide, SO 3, is produced as a gas and dissolves in atmospheric Modern Chemistry 230 Answer Key

6 TEACHER RESOURCE PAGE water to produce a sulfuric acid solution that falls to the ground as rain or snow. SO 3 (g) H 2 O(l) H 2 SO 4 (aq) 37. Have a sour taste; change the color of acid-base indicators; some react with active metals to release hydrogen gas; react with bases to produce salts and water; conduct electric current 38. H 3 PO 4 (aq) H 2 O(l) H 3 O (aq) H 2 PO 4 (aq) H 2 PO 4 (aq) H 2 O(l) H 3O (aq) HPO 4 2 (aq) HPO 4 2 (aq) H 2 O(l) H 3O (aq) PO 4 3 (aq) 15 Acid-Base Titration and ph, pp TEST A 1. d 2. c 3. b 4. c 5. c 6. c 7. b 8. b 9. d 10. b 11. c 12. b 13. a 14. d 15. d 16. d 17. d 18. a 19. c 20. c 21. d 22. b 23. c 24. d 25. d TEST B 1. d 2. b 3. d 4. c 5. a 6. b 7. a 8. d 9. self-ionization 10. basic 11. transition interval 12. ph decreases 16. end point 17. higher 18. lower 19. primary standard 20. higher 21. acidic 22. acidic 23. acidic 24. basic 25. basic 26. A ph meter measures the ph of a solution by measuring the voltage between the two electrodes that are placed in the solution. This works because the voltage is proportional to the hydronium ion concentration. 27. The ph changes slowly at first, then rapidly through the equivalence point, then slowly again. 28. HIn H 2 O H 3O In or HIn ^ H In In acidic solutions, the H 3 O ions in solution drive the equation toward the nonionized form. HIn is present in largely nonionized form in acidic solutions, and In ions are present in largely ionized form in basic solutions. HIn is a different color than the In ion. 29. acidic 30. neutral 31. basic 32. basic 33. basic 34. [H 3 O ] M; [OH ] M 35. [H 3 O ] M; [OH ] M 36. [H 3 O ] M; [OH ] M 37. [H 3 O ] M; [OH ] M 38. [H 3 O ] M; [OH ] M M M M M M 16 Reaction Energy, pp TEST A 1. d 2. a 3. c 4. a 5. b 6. c 7. a 8. a Modern Chemistry 231 Answer Key