SCHOOL YEAR CH- 13 IONS IN AQUEOUS SOLUTIONS AND COLLIGATIVE PROPERTIES SUBJECT: CHEMISTRY GRADE : 11 TEST A

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1 SCHOOL YEAR NAME: CH- 13 IONS IN AQUEOUS SOLUTIONS AND COLLIGATIVE PROPERTIES SUBJECT: CHEMISTRY GRADE : 11 TEST A Choose the best answer from the options that follow each question. 1. A solute whose water solution conducts electricity is called a(n) a. nonconductor. b. electrolyte. c. nonelectrolyte. d. aqueous solution. 2. Which solution has the highest boiling point? a m glucose in water b m potassium iodide in water c m glucose in water d m calcium chloride in water 3. When an ionic solid dissolves in water, which of the following does not occur? a. The compound dissociates. b. Hydration occurs. c. The compound ionizes. d. Polar ends of water molecules approach the ions, releasing energy. 4. Colligative properties depend on the a. number of solute particles present. b. size of solute particles present. c. mass of solute particles present. d. charge on solute particles present. 5. Nonvolatile solutes a. depress both the freezing point and the boiling point. b. elevate both the freezing point and the boiling point. c. depress the freezing point and elevate the boiling point. d. elevate the freezing point and depress the boiling point.

2 Use the table to answer the following questions. Solubility Rules for Some Common Ionic Compounds Compounds containing these ions are soluble in water: Alkali metals (Group 1), except LiF Ammonium, NH + Bromides, Br, except those of Ag +, Pb 2+, and Hg Chlorides, Cl, except those of Ag +, Pb 2+, and Hg Nitrates, NO Sulfates, SO, except those of Ca 2+, Sr 2+, Ba 2+, Pb 2+, and Hg Compounds containing these ions are insoluble in water: Carbonates, CO Hydroxides, OH, except those of Group 1 Oxides, O 2 Phosphates, PO, except those of Group 1, Ca 2+, Sr 2+, and Ba 2+ (which form hydroxides), except those of Group 1 and NH Sulfides, S 2, except those of Group 1, Mg 2+, Ca 2+, Ba 2+, and NH 6. Using the table above, which of the following compounds is soluble in water? a. PbBr 2 b. MgCl 2 c. BaSO 4 d. CaCO 3 7. Using the table above, which of the following compounds is insoluble in water? a. (NH 4 ) 2 S b. Na 2 O c. LiOH d. Al 2 O 3 Choose the best answer from the options that follow each question. 8. Compared with the freezing-point depression of a 0.01 m C 6 H 12 O 6 solution, the freezing-point depression of a 0.01 m NaCl solution is a. almost half. b. exactly the same. c. exactly twice as great. d. almost twice as great. 9. Which of the following is an ionic compound that dissociates in water? a. NaCl b. C1 2 c. CCl 4 d. C 6 H 6

3 10. Which of these is a spectator ion in the following equation? a. S b. Cu 2+ c. Zn 2+ d. None of the above Cu 2+ (aq) Zn 2 (aq) + 2S (aq) CuS(s) + ZnS(s) 11. What happens when a weak electrolyte dissolves in water? a. The boiling point decreases. b. The solution does not conduct electricity. c. Few ions form. d. 100% of the molecules ionize. 12. What is the freezing point of a 1.5 m solution of sucrose in water? (Kf = 1.86C /m) a. 2.8 C b. 1.2 C c C d C 13. What concentration of ethylene glycol is needed to raise the boiling point of water to 105 C? (K b C /m) a. 1.5 m b. 2.5 m c. 9.8 m d. 205 m 14. Compared with a 1.0 m solution of C 12 H 22 O 11, the vapor pressure of a 1.0 m solution of C 5 H 12 O 6 a. is exactly double. b. is the same. c. is exactly half. d. cannot be determined. 15. How many moles of Cl ions are produced when 0.5 mol of NaCl is dissolved in water? a. 0.5 b. 1.0 c. 1.5 d What is the net ionic equation for the precipitation reaction between BaCl 2 and Na 2 SO 4? a. Ba 2 (aq) + SO (aq) BaSO 4 (s) b. Na + (aq) + Cl(aq) NaCl(s) c. Ba 2+ (aq) + 2Cl (aq) + 2Na + (aq) + SO (aq) BaSO 4 (s) + 2Cl (aq) + 2Na + (aq) d. BaCl 2 (aq) + Na 2 SO 4 (aq) BaSO 4 (s) + 2NaCl(aq) 17. Which solute will have the greatest effect on the boiling point of water? a. C 6 H 12 O 6 b. NaCl c. HF d. CH 3 COOH

4 18. What is the approximate freezing-point depression of a 0.10 m aqueous CaCl 2 solution? (K f = 1.86C /m) a C b C c C d C 19. The external pressure that must be applied to stop osmosis is called a. atmospheric pressure. b. vapor pressure. c. osmotic pressure. d. None of the above 20. Electrolytes have a greater effect on colligative properties than nonelectrolytes do because electrolytes a. are volatile. b. have higher boiling points. c. produce fewer moles of solute particles per mole of solvent. d. produce more moles of solute particles per mole of solvent. 21. A 12 m acetic acid solution is a. concentrated and a weak electrolyte. b. dilute and a weak electrolyte. c. concentrated and a strong electrolyte. d. dilute and a strong electrolyte. 22. A 2 m solution contains a. 2 mol of solute dissolved in 1 L of solvent. b. 1 mol of solute dissolved in 2 L of solvent. c. 2 mol of solute dissolved in 1 mol of solvent. d. 2 mol of solute dissolved in 1 kg of solvent. 23. What is the boiling-point elevation of a solution made from 15.0 g of a nonelectrolyte solute and g of water? The molar mass of the solute is 50.0 g and K b = 0.51 C/m. a C b C c C d C 24. The hydronium ion forms when hydrogen ions a. dissociate. b. ionize. c. combine with HCl. d. combine with H 2 O. 25. What is the expected boiling point of a solution of 128 g KCl (a strong electrolyte) dissolved in 1.3 kg of water. The molar mass of KCl is g and K b = 0.51C /m. a C b C c C d C

5 TEST B PART I Choose the best answer from the options that follow each question. 1. A colligative property is one that depends on a. the number of solute particles but not their identity. b. the identity of solute particles but not their number. c. both the number and the identity of solute particles. d. neither the number nor the identity of solute particles. 2. Which of the following is not a colligative property? a. boiling-point elevation b. lowering vapor pressure c. freezing-point depression d. conducting electricity 3. How many moles of ions are produced when 2 mol of Na 2 CO 3 dissociate? a. 2 b. 3 c. 6 d If the following equation were written as a net ionic equation, which ion(s) is (are) the spectator ion(s)? Zn(s) + CuSO 4 (aq) Cu(s)ZnSO 4 (aq) a. Cu 2+ (aq) b. Zn 2+ (aq) c. SO (aq) d. All of the above 5. To determine the molar mass of a solute by using colligative properties, you must know the a. volume of the solution. b. mass of the solute. c. temperature of the solution. d. volume of the solute. 6. What is the net ionic equation for the precipitation reaction between silver nitrate solution and sodium sulfide solution? a. 2Ag + (aq) + 2NO (aq) + 2Na + (aq) + S 2 (aq) Ag 2 S(s) + 2Na + (aq) b. c. d. 2Ag + (aq) +S 2 (aq) Ag 2 S(s) 2Ag + (aq) + 2NO (aq) + 2Na + (aq) + S 2 (aq) Ag 2 S(s) + 2NaNO 3 (s) + S 2 (aq) 2Ag (aq) + S 2+ (aq) Ag 2 S(s) 7. Which ions are not spectator ions for the precipitation reaction that occurs when solutions of Zn(NO 3 ) 2 and Na 3 PO 4 are mixed? a. Zn 2+ (aq) and NO (aq) b. Na + (aq) and Zn 2+ (aq) c. Zn 2+ (aq) and PO (aq)

6 d. Na + (aq) and NO (aq) 8. When nonvolatile, nonionic solutes are added to water, they a. depress freezing point and elevate boiling point. b. elevate freezing point and depress boiling point. c. depress both freezing and boiling points. d. elevate both freezing and boiling points. PART II Write the correct term (or terms) in the space provided. 9. When a solid is formed from the combination of two solutions of ionic compounds, it is called. 10. allow the movement of some particles while blocking the movement of others. 11. Any substance whose water solution conducts electricity is a(n). 12. An ion that does not take part in a chemical reaction is called a(n). 13. The number of moles of ions produced by the dissociation of 1 mol of MgCl 2 is. 14. is the external pressure that must be applied to stop osmosis. 15. The symbol for the hydronium ion is. 16. The ions Ca 2+ (aq) and NO (aq) are produced by the dissociation of the compound whose formula is. 17. The vapor pressure of pure water is than the vapor pressure for an aqueous solution. 18. The boiling point for a 1 M solution of glucose (a nonelectrolyte) will be than for a 1 M solution of NaCl (a strong electrolyte). 19. The right-hand side of the equation for the dissolving of K 2 S is. PART III Write the answers to the following questions. 20. Explain how ionization and dissociation differ. 21. Distinguish between the dissolution of a strong electrolyte and that of a weak electrolyte. 22. Why is the hydronium ion used to represent the hydrogen ion in a solution? 23. Explain why salt is frequently poured on icy roads in the winter. PART IV For the following questions, use the guidelines below to determine which of the following combinations of solutions will produce a precipitate. If no precipitate will form, write none. If a precipitate will form, write the net ionic equation for the reaction.

7 General Solubility Guidelines 1. Most sodium, potassium, and ammonium compounds are soluble in water. 2. Most nitrates, acetates, and chlorates are soluble. 3. Most chlorides are soluble except those of silver, mercury(ii), and lead. Lead(II) chloride is soluble in hot water. 4. Most sulfates are soluble except those of calcium, barium, strontium, and lead. 5. Most carbonates, phosphates, and silicates are insoluble except those of sodium, potassium, and ammonium. 6. Most sulfides are insoluble except those of calcium, strontium, sodium, potassium, and ammonium. 24. KCl and Ca(NO 3 ) Na 2 SO 4 and BaCl (NH 4 ) 2 S and Cd(NO 3 ) NH 4 Cl and Na 2 SO Ca(NO 3 ) 2 and CuCl A solution with 3.11 g of a nonelectrolyte solute in 38 g of water (K b = 0.51 C/m) has a boiling point elevated by 1.00 C. What is the molar mass of the solute? 30. The boiling point of a solvent is elevated by 2.4 C when the solute concentration is 3.1 m. What is K b? 31. What is the freezing-point depression of a solution that contains mol of a nonelectrolyte solute in 5.02 kg of water? (K f 1.86 C/m) 32. The freezing point of a solvent is lowered by 2.89 C when the solute concentration is 1.03 m. What is K f? 33. How many grams of a nonelectrolyte solute that has a molar mass of 41.9 g/mol must be added to g of water to raise the boiling point 0.84 C? (K b 0.51C /m) 34. What is the boiling-point elevation of water for a solution that contains 125 g of barium nitrate, Ba(NO 3 ) 2, dissolved in 1.00 kg of water? The molar mass of the solute is g/mol. (K b = 0.51 C/m)

8 SCHOOL YEAR NAME: CH- 14 ACIDS AND BASESE SUBJECT: CHEMISTRY GRADE : 11 TEST A Choose the best answer from the options that follow 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 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 (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 (aq)

9 c. CH 3 NH 2 (aq) and CH 3 NH (aq) d. HC 2 O (aq) and CH 3 NH (aq) 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 8. 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. 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.

10 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 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. 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 (aq) Which substances are present in the greatest concentrations? a. HClO 4 and H 2 O b. HClO 4 and ClO c. H 3 O + and ClO

11 d. H 2 O and H 3 O Consider the two equations below. H 2 SO 4 (aq) + H 2 O(l) H 3 O + (aq) + HSO (aq) NH 3 (g) + H 2 O(l) NH (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 (aq) + K + (aq) KNO 3 (aq) b. H 3 O + (aq) + OH (aq) 2H 2 O(l) c. H 3 O + (aq) + NO (aq) + K + (aq) + OH (aq) NO (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. HS(aq). c. H 3 O + (aq). d. SO (aq).

12 TEST B PART I Choose the best answer from the options that follow each question. 1. Which of the following is an oxyacid? a. HCl b. H 2 O c. H 2 S d. H 2 SO 4 2. Which acid is produced in the stomach? a. HNO 3 b. CH 3 COOH c. H 2 SO 4 d. HCl 3. Which of the following is a strong base? a. NH3 b. aniline c. NaOH d. acetate ion 4. In the reaction represented by the equation HF(aq) + H 2 O(l) H 3 O + (aq) + F (aq), a conjugate acid-base pair is a. F and H 2 O. b. H 3 O + and HF. c. HF and F. d. HF and H 2 O. 5. If H 2 O in the reaction represented by the equation H 2 O + C 2 H 3 COOH H 3 O + + C 2 H 3 COO is considered to be a weaker base, then H 3 O is a a. stronger acid. b. stronger base. c. weaker acid. d. weaker base. 6. Proton-transfer reactions favor production of the a. stronger acid and stronger base. b. weaker acid and weaker base. c. stronger acid and weaker base. d. weaker acid and stronger base. 7. Aqueous solutions of most bases contain a. hydroxide ions and cations. b. hydroxide ions and anions. c. hydrogen ions and anions. d. hydrogen ions and cations. 8. Acid strength increases with a. increasing polarity and increasing bond strength. b. increasing polarity and decreasing bond strength. c. decreasing polarity and increasing bond strength.

13 d. decreasing polarity and decreasing bond strength. PART II Write the correct term (or terms) in the space provided. 9. A substance that ionizes almost completely in aqueous solutions, producing H 3 O + ions, is a(n) acid. 10. An acid that contains hydrogen and only one other element is called a(n) acid. 11. The species that forms when an acid has given up a proton is called the acid s. 12. An acid that can donate two protons per molecule is called a(n) acid. 13. Bases are said to be neutralized when they react with to yield and a(n). 14. Any species that can react as either an acid or a base is described as. 15. Barium carbonate will react with hydrochloric acid to produce,, and. PART III Write the name of each of the following acids in the space provided. 16. HNO HCl 18. H 2 CO H 2 SO HI 21. HBrO Write the formula for each of the following acids in the space provided. 22. hydrosulfuric acid 23. nitric acid 24. phosphorous acid 25. perchloric acid Refer to the equation below to answer the following questions. HCl(g) + NH 3 (l) NH (aq) + Cl (aq)

14 26. List the conjugate acid-base pairs. 27. Identify each reactant and product as acidic or basic. Refer to the equation below to answer the following questions. H 2 O(l) + NH 3 (g) NH (aq) + OH (aq) 28. List the conjugate acid-base pairs. 29. Identify each reactant and product as a proton donor or a proton acceptor. Refer to the following statement to answer the following questions: Dilute HCl(aq) and NaOH(aq) are mixed in chemically equivalent quantities 30. Write the chemical equation for the reaction. 31. Write the overall ionic equation for the reaction. 32. Write the net ionic equation. Use the following three acids to answer the following questions. 33. Give the formulas for these three acids. iodic acid hypoiodous acid periodic acid 34. List the acids in order of increasing acid strength. PART IV Write the answers to the following questions in the space provided. 35. Explain the difference between strong acids and weak acids. 36. Explain how the production of sulfur trioxide, SO 3, in industrial processes can result in acid rain. Write an equation for the reaction. 37. List five properties of aqueous acids. 38. Write the balanced equations that describe the three-stage ionization of phosphoric acid in a dilute aqueous