CHM 122 Assessment on Phenols - Chpt 11 Ionic Equilibra PDF

gifted CHM 122 assessment on the topic phenols Chpt 11 Ionic Equilibra Time: 1 Hours Full Marks: 100 1. 1. W...

gifted CHM 122 assessment on the topic phenols Chpt 11 Ionic Equilibra Time: 1 Hours Full Marks: 100 1. 1. What is the main characteristic of electrolytes? (a) a) They dissociate into (b) b) They are only slightly (c) c) They do not dissociate (d) d) They do not conduct charged particles. soluble in water. in solution. electricity. 2. 2. Which of the following is an example of a strong electrolyte? (a) a) NaCl (b) b) CH₃COOH (c) c) NH₄OH (d) d) H₂O 3. 3. The Van’t Hoff factor (i) is a correction factor necessary for which type of solutions? (b) b) Non-electrolyte (a) a) Electrolyte solutions (c) c) Organic solutions (d) d) Dilute solutions solutions 4. 4. What is the degree of dissociation of an electrolyte? (a) a) The fraction of (b) b) The total number of (c) c) The molality of the (d) d) The temperature of the dissociation of the electrolyte ions produced solution solution 5. 5. The Van't Hoff factor (i) for a dissociating electrolyte is always: (a) a) Greater than 1 (b) b) Equal to 1 (c) c) Less than 1 (d) d) Zero 6. 6. What does the percent degree of dissociation refer to? (a) a) The percentage of (b) b) The concentration of (c) c) The temperature (d) d) The molality of the solute that dissociates into the electrolyte in solution. change of the solution. solution. ions. 7. 7. For a given solution, what determines the degree of dissociation? (c) c) Concentration of the (a) a) Nature of the solute (b) b) Nature of the solvent (d) d) All of the above solute 8. 8. The degree of dissociation of acetic acid in a 1 M solution is: (a) a) 0.4% (b) b) 100% (c) c) 75% (d) d) 50% 9. 9. What effect does decreasing the concentration of a solute have on its degree of dissociation? (c) c) The degree of (a) a) The degree of (b) b) The degree of (d) d) It depends on the dissociation remains dissociation increases. dissociation decreases. solute. unchanged. 10. 10. Which of the following solutes is considered a weak electrolyte? (a) a) CH₃COOH (b) b) NaCl (c) c) NaOH (d) d) HCl 11. 11. Which factor primarily determines the dissociation of an electrolyte in a solution? (a) a) Nature of the solute and (b) b) Pressure (c) c) Particle size (d) d) Molecular weight solvent 12. 12. What is the effect of temperature on the dissociation of electrolytes? (a) a) It may either increase or (b) b) It always decreases (c) c) It always increases (d) d) Temperature has no decrease dissociation dissociation. dissociation. effect on dissociation. depending on the substance. 13. 13. What is the difference between dissociation and ionization? (a) a) Ionization is the (d) d) There is no difference (b) b) Dissociation occurs (c) c) Ionization does not dissociation of particles into between dissociation and only in ionic compounds. involve charged particles. charged ions. ionization. 14. 14. Which of the following is an example of dissociation without ionization? (a) a) PCl₅ → PCl₄⁺ + Cl⁻ (b) b) HCl → H⁺ + Cl⁻ (c) c) NaCl → Na⁺ + Cl⁻ (d) d) Na₂SO₄ → 2Na⁺ + SO₄²⁻ 15. 15. In concentrated solutions, ionization can be incomplete due to the formation of: (a) a) Ion pairs (b) b) Solvent molecules (c) c) Non-electrolytes (d) d) Acidic molecules 16. 16. Which of the following solutions would have no electrical conductivity? (a) a) A solution containing (b) b) A solution with no ions (c) c) A solution of NaCl (d) d) A solution of HCl only ion pairs present 17. 17. The ionization equilibrium constant is represented as: (a) a) Kₐ (b) b) Ksp (c) c) Ka (d) d) Keq 18. 18. For weak electrolytes, the ionic concentrations are: (d) d) Independent of the (a) a) Low (b) b) High (c) c) Equal to the molality solvent 19. 19. What is the main assumption for calculating the ionization equilibrium constant for weak electrolytes? (a) a) The activity coefficient (b) b) The electrolyte is fully (d) d) The solution is (c) c) The solution is dilute. is close to unity. dissociated. concentrated. 20. 20. The solubility of a sparingly soluble salt is calculated based on: (a) a) Its solubility product (b) b) The temperature of the (c) c) The concentration of (d) d) The molecular weight of (Ksp) solution the solvent the solute 21. 21. What type of equilibrium exists in a saturated solution of a sparingly soluble salt? (a) a) Heterogeneous (b) b) Homogeneous (c) c) Dynamic equilibrium (d) d) Static equilibrium equilibrium equilibrium 22. 22. For a salt with the formula AB, the equilibrium for its solubility is represented by: (c) c) AB(aq) → A⁺(aq) + (a) a) AB(s) ⇌ A⁺(aq) + B⁻(aq) (b) b) AB(s) → A⁺(aq) + B⁻(aq) (d) d) AB(s) → AB(aq) B⁻(aq) 23. 23. What is the solubility product (Ksp) used to describe? (a) a) The equilibrium (c) c) The degree of (b) b) The ionization constant (d) d) The concentration of between a solid salt and its dissociation of a strong of acids ions in a neutral solution ions in solution electrolyte 24. 24. In a solution of a 1:1 salt like NaCl, the solubility product (Ksp) is equal to: (a) a) S² (b) b) 2S (c) c) S³ (d) d) 2S² 25. 25. For a salt with the formula FeCl₂, what would be the relationship between the solubility (S) and the ions produced? (a) a) The concentration of (b) b) The concentration of Fe²⁺ ions is S, and the (c) c) Both Fe²⁺ and Cl⁻ have (d) d) Both Fe²⁺ and Cl⁻ have Fe²⁺ ions is 2S, and the concentration of Cl⁻ ions is concentrations of S. concentrations of 2S. concentration of Cl⁻ ions is S. 2S. 26. 26. The solubility of a slightly soluble salt can be affected by: (a) a) The presence of (b) b) The temperature (c) c) The pH of the solution (d) d) All of the above common ions 27. 27. In which case will a salt's solubility decrease due to the common ion effect? (a) a) When the concentration (b) b) When the concentration (c) c) When the temperature of one of the ions already (d) d) When the salt is diluted. of the solvent increases. increases. present in the salt increases. 28. 28. The concentration of ions in a saturated solution of a slightly soluble salt is: (a) a) Directly proportional to (b) b) Inversely proportional (c) c) Unaffected by the (d) d) Zero the solubility to the solubility solubility 29. 29. Which factor does NOT significantly affect the solubility of a salt? (b) b) The temperature of the (c) c) The concentration of (d) d) The presence of a (a) a) The size of the ions solution the solvent common ion 30. 30. What is the solubility of a salt with a Ksp value of 1.6 × 10⁻⁹, assuming it dissociates into two ions? (a) a) 4.0 × 10⁻⁵ mol/L (b) b) 1.6 × 10⁻⁶ mol/L (c) c) 2.0 × 10⁻⁴ mol/L (d) d) 1.0 × 10⁻⁴ mol/L 31. 1. What is the common ion effect in solubility? (a) A) The solubility of an (b) B) The solubility of an (d) D) It affects only the (c) C) It has no effect on ionic salt decreases when a ionic salt increases when a concentration of ions in the solubility. common ion is added. common ion is added. solution. 32. 2. What happens when chloride ion is added to a saturated solution of silver chloride? (a) A) The equilibrium shifts (b) B) The solubility of silver (c) C) The concentration of (d) D) The solution becomes to the left, and some silver chloride increases. silver ion increases. more acidic. chloride precipitates. 33. 3. Which of the following is a correct description of the solubility product (Ksp)? (a) A) Ksp is the product of (c) C) Ksp is the (b) B) Ksp only applies to (d) D) Ksp is a constant only the concentrations of the ions concentration of the solute in acids and bases. for gases. in a saturated solution. a non-saturated solution. 34. 4. What occurs when the ionic product exceeds Ksp? (a) A) Precipitation of the salt (b) B) More solute dissolves (c) C) The solution becomes (d) D) The solution becomes occurs. to restore equilibrium. less acidic. neutral. 35. 5. How does the solubility product principle apply to the precipitation of salts? (a) A) Precipitation occurs (b) B) Precipitation occurs (c) C) Precipitation is (d) D) Precipitation requires when the ionic product when the ionic product is less independent of the ionic the addition of a common ion. exceeds Ksp. than Ksp. product. 36. 6. Which of the following substances will reduce the solubility of silver chromate (Ag2CrO4) in solution? (a) A) The addition of a (b) B) The addition of NaOH. (c) C) The addition of water. (d) D) The addition of NH3. common ion like Ag+. 37. 7. What is the primary purpose of the solubility product principle? (a) A) To predict the (c) C) To measure the (b) B) To determine the (d) D) To calculate the pH of a formation of a precipitate in a concentration of ions in ionization constants of acids. solution. solution. solution. 38. 8. In a solution of Ag2CrO4, what happens if NaCl is added? (a) A) The solubility of (b) B) The solubility of (d) D) The solution becomes Ag2CrO4 decreases due to (c) C) No change occurs. Ag2CrO4 increases. acidic. the common ion effect. 39. 9. What happens when NH3 is added to a saturated solution of AgCl? (a) A) The solubility of AgCl (b) B) The solubility of AgCl (c) C) The solution turns (d) D) The silver chloride increases due to the decreases. yellow. precipitates. formation of a complex ion. 40. 10. How is the concentration of an ion affected when the solubility product is exceeded? (a) A) The concentration of (b) B) The concentration of (c) C) The concentration of (d) D) The ion undergoes the ion will decrease as the the ion increases the ion remains unaffected. neutralization. salt precipitates. continuously. 41. 11. What is the effect of adding NaNO3 to a saturated solution of AgCl? (a) A) The solubility of AgCl (b) B) The solubility of AgCl (d) D) AgCl will precipitate will decrease due to the (c) C) No change occurs. will increase. completely. common ion effect. 42. 12. What does the solubility product constant (Ksp) indicate in an equilibrium system? (a) A) It represents the (b) B) It represents the (d) D) It indicates the maximum concentration of minimum concentration of (c) C) It indicates the pH of concentration of the solid ions that can exist in a ions that can exist in a the solution. salt. saturated solution. saturated solution. 43. 13. What is the solubility of silver chromate (Ag2CrO4) in pure water at 25°C if Ksp = 9.0 × 10^-12? (a) A) 6.92 × 10^-4 mol/dm^3. (b) B) 9.0 × 10^-12 mol/dm^3. (c) C) 1.0 × 10^-5 mol/dm^3. (d) D) 4.0 × 10^-12 mol/dm^3. 44. 14. Which factor increases the solubility of a slightly soluble salt? (a) A) Addition of a (b) B) Addition of a common (c) C) Decreasing (d) D) Increasing pressure. complexing agent like NH3. ion. temperature. 45. 15. What happens to the solubility of ZnS in the presence of a common ion like Zn2+? (a) A) The solubility (b) B) The solubility (d) D) ZnS precipitates (c) C) No change occurs. decreases. increases. completely. 46. 16. What is the effect of the presence of NaOH in a solution of H2SO4 (sulfuric acid)? (a) A) NaOH neutralizes the (b) B) NaOH increases the (c) C) NaOH makes the (d) D) NaOH forms a acid and forms a salt. acidity of the solution. solution more basic. precipitate of sodium sulfate. 47. 17. What is the correct dissociation of H2SO4 in water? (a) A) H2SO4 → H+ + HSO4^- (b) B) H2SO4 → 2H+ + (c) C) H2SO4 → H2SO3 + O2. (d) D) H2SO4 → H+ + SO3^2-. → 2H+ + SO4^2-. SO4^2-. 48. 18. What is the definition of a polyprotic acid? (a) A) An acid that can donate (b) B) An acid that only (c) C) An acid that does not (d) D) An acid that more than one proton per donates one proton per dissociate in water. dissociates into two acids. molecule. molecule. 49. 19. What is the amphoteric behavior of water? (a) A) Water can act as both (b) B) Water only acts as an (c) C) Water only acts as a (d) D) Water does not an acid and a base. acid. base. dissociate in solution. 50. 20. What is the ionization constant of H2SO4 in its first dissociation step? (a) A) k1 > k2 > k3. (b) B) k1 = k2 = k3. (c) C) k1 < k2 < k3. (d) D) k1 = 0. 51. 21. Which of the following is true about weak acids in water? (a) A) Weak acids are only (b) B) Weak acids completely (c) C) Weak acids do not (d) D) Weak acids neutralize slightly ionized in water. ionize in water. affect the pH of water. bases completely. 52. 22. How does NH3 act as a base in water? (a) A) NH3 accepts a proton (b) B) NH3 donates a proton (c) C) NH3 forms a complex (d) D) NH3 does not react to form NH4+. to form NH2^-. with H+ to become neutral. with water. 53. 23. What is the result when CO2 dissolves in water? (a) A) It forms H2CO3, which (b) B) It forms CO3^2-, which increases the H+ decreases the H+ (c) C) It increases the pH. (d) D) It has no effect on pH. concentration. concentration. 54. 24. Which of the following compounds acts as an acid in water according to the Brønsted-Lowry definition? (a) A) HCl. (b) B) NH3. (c) C) NaOH. (d) D) Na2CO3. 55. 25. What is the Brønsted-Lowry definition of an acid? (a) A) A substance that (b) B) A substance that (c) C) A substance that (d) D) A substance that donates a proton. accepts a proton. increases OH- concentration. dissociates into ions. 56. 26. What is a conjugate base? (a) A) The species formed (b) B) The species formed (c) C) The species formed (d) D) The species formed when an acid donates a when a base donates a when an acid accepts a when a base accepts a proton. proton. proton. proton. 57. 27. What type of reaction occurs when an acid and a base react together according to Brønsted-Lowry? (a) A) A proton transfer (b) B) A redox reaction. (c) C) A precipitation reaction. (d) D) A dissociation reaction. (neutralization). 58. 28. How does NH4Cl act in water? (c) C) It dissociates into (a) A) It forms NH4+ and Cl-, (b) B) It forms NH3 and Cl-, (d) D) It does not dissociate in NH4+ and OH-, making the making the solution acidic. making the solution basic. water. solution basic. 59. 29. What is the main feature of a Lewis acid-base reaction? (a) A) A Lewis acid accepts (b) B) A Lewis acid donates a (c) C) A Lewis acid forms a (d) D) A Lewis acid increases an electron pair from a Lewis proton to a Lewis base. precipitate with a base. the concentration of OH-. base. 60. 30. In the reaction between Na2S and H2O, what type of solution is formed? (a) A) A basic solution due to (b) B) An acidic solution due (c) C) A neutral solution with (d) D) A solution with a strong the production of OH- ions. to the production of H+ ions. no change in pH. odor. 61. 1. According to the Lewis definition of acids and bases, an acid is a substance that: (a) a) Accepts an electron (b) b) Donates an electron (c) c) Increases the (d) d) Reduces the pair pair concentration of H+ ions concentration of OH- ions 62. 2. What is the ion product constant (Kw) of water at 25°C? (a) a) 1.0 x 10^-14 (b) b) 1.0 x 10^-7 (c) c) 1.0 x 10^-12 (d) d) 1.0 x 10^0 63. 3. A solution with a pH of 3 is: (a) a) Acidic (b) b) Neutral (c) c) Basic (d) d) Alkaline 64. 4. The pH scale was introduced by: (a) a) Sorensen (b) b) Lewis (c) c) Arrhenius (d) d) Bronsted-Lowry 65. 5. What is the pOH of a solution with an OH- concentration of 1 x 10^-4 M? (a) a) 10 (b) b) 4 (c) c) 7 (d) d) 14 66. 6. Which of the following acids has the smallest ionization constant (Ka)? (a) a) HCN (b) b) HCl (c) c) HNO3 (d) d) H2SO4 67. 7. A weak acid, such as acetic acid, dissociates in water to form: (a) a) H+ and Ac- ions (b) b) H+ and OH- ions (c) c) NH3 and H2O (d) d) H2SO4 and H2O 68. 8. The formula for calculating pH is: (a) a) -log[H+] (b) b) log[H+] (c) c) -log[OH-] (d) d) log[OH-] 69. 9. Which of the following is a characteristic of a strong acid? (a) a) High dissociation in (b) b) Low dissociation in (c) c) Small Ka value (d) d) Strong base behavior water water 70. 10. The dissociation constant for a weak base is known as: (a) a) Kb (b) b) Ka (c) c) Kw (d) d) pKa 71. 11. The relationship between pH and pOH is: (a) a) pH + pOH = 14 (b) b) pH + pOH = 1 (c) c) pH + pOH = 7 (d) d) pH + pOH = 10 72. 12. In a neutral solution at 25°C, the concentration of H+ ions is: (a) a) 1 x 10^-7 M (b) b) 1 x 10^-14 M (c) c) 0 M (d) d) 1 M 73. 13. Which of the following bases has the largest ionization constant (Kb)? (a) a) Pyridine (b) b) Ethylamine (c) c) NH4OH (d) d) Aniline 74. 14. The ionization of a weak acid is described by: (a) a) Ka = [H+][Ac-] / [HAc] (b) b) Ka = [H+][OH-] / [H2O] (c) c) Ka = [H+][HAc] / [Ac-] (d) d) Ka = [OH-][HAc] / [H+] 75. 15. What is the pH of a 0.010 M HCl solution? (a) a) 2 (b) b) 3 (c) c) 4 (d) d) 1 76. 16. Which of the following compounds is considered a weak base? (a) a) NH3 (b) b) NaOH (c) c) KOH (d) d) Na2CO3 77. 17. The degree of ionization (α) of a weak acid is defined as: (a) a) x / C (b) b) x / V (c) c) C / x (d) d) C / V 78. 18. The concentration of OH- ions in a neutral solution is: (a) a) 1 x 10^-7 M (b) b) 1 x 10^-14 M (c) c) 1 x 10^-3 M (d) d) 1 x 10^0 M 79. 19. The pKa of an acid is related to: (c) c) Its dissociation in a (a) a) Its strength (b) b) Its solubility (d) d) Its color solvent 80. 20. What is the relationship between pKa and acid strength? (a) a) The smaller the pKa, the (b) b) The larger the pKa, the (c) c) The smaller the pKa, the (d) d) The pKa has no effect stronger the acid stronger the acid weaker the acid on acid strength 81. 21. A solution of NaOH in water increases the concentration of: (a) a) OH- ions (b) b) H+ ions (c) c) Na+ ions (d) d) Water molecules 82. 22. For a weak acid with a very small Ka value, the degree of ionization is: (a) a) Very small (b) b) Very large (c) c) Equal to one (d) d) Zero 83. 23. What happens when a base is added to water? (a) a) OH- concentration (b) b) OH- concentration (c) c) H+ concentration (d) d) H+ concentration increases decreases increases remains the same 84. 24. The degree of ionization is represented by: (a) a) α (b) b) Ka (c) c) pKa (d) d) Kb 85. 25. The concentration of H+ ions in a solution with pH = 9 is: (a) a) 1 x 10^-9 M (b) b) 1 x 10^-7 M (c) c) 1 x 10^-14 M (d) d) 1 x 10^-3 M 86. 26. Which of the following is true for a neutral solution at 25°C? (a) a) [H+] = [OH-] (b) b) [H+] > [OH-] (c) c) [OH-] > [H+] (d) d) [H+] = 0 87. 27. In an acid-base titration, an indicator is used to: (a) a) Detect the end point of (b) b) Increase the (d) d) Change the color of the (c) c) Speed up the reaction the reaction concentration of acid solution 88. 28. What is the pH of a solution with an H+ concentration of 1 x 10^-8 M? (a) a) 8 (b) b) 7 (c) c) 9 (d) d) 14 89. 29. The ionization constant for water is represented by: (a) a) Kw (b) b) Ka (c) c) Kb (d) d) Kc 90. 30. Which of the following is true about a weak acid solution? (b) b) It dissociates (c) c) It has a large (d) d) It is a strong conductor (a) a) It has a small Ka value completely concentration of H+ ions of electricity 91. 1. What is the ionization constant (K) for a weak acid, as described in the text? (a) a) K = 85 x 10^-9 (b) b) K = 1 x 10^-7 (c) c) K = 10^-5 (d) d) K = 1 x 10^-6 92. 2. What is the degree of ionization of hydrogen acetate in a solution? (a) a) 1.8 x 10^-4 (b) b) 2.5 x 10^-5 (c) c) 5.0 x 10^-6 (d) d) 9.2 x 10^-3 93. 3. Which of the following indicators changes color in the pH range 3.1 to 4.4? (a) a) Methyl orange (b) b) Phenolphthalein (c) c) Phenol red (d) d) Methyl red 94. 4. What is the acid color of methyl orange in an acidic solution? (a) a) Red (b) b) Yellow (c) c) Orange (d) d) Blue 95. 5. Which of the following is the correct equilibrium for a weak acid indicator in water? (a) a) HIn ⇌ H+ + In- (b) b) HIn ⇌ H+ + OH- (c) c) H2O ⇌ H+ + OH- (d) d) HIn ⇌ OH- + In- 96. 6. What causes the shift in the equilibrium of an indicator in an acidic solution? (a) a) Excess H+ ions (b) b) Excess OH- ions (c) c) Water molecules (d) d) The salt dissociates in suppress ionization promote ionization suppress the reaction acid 97. 7. In an alkaline medium, what happens to the ionization of an indicator? (a) a) It increases (b) b) It decreases (c) c) It remains constant (d) d) It becomes negligible 98. 8. What type of acid-base indicator is typically used for titrations involving strong acids and weak bases? (a) a) Methyl orange (b) b) Phenolphthalein (c) c) Phenol red (d) d) Methyl red 99. 9. What is the effect of salt hydrolysis on the pH of a solution? (a) a) It can produce a weak (b) b) It always results in a (c) c) It decreases the (d) d) It increases the acid or weak base neutral solution concentration of H+ ions concentration of OH- ions 100. 10. In a titration of a strong acid with a weak base, the equivalence point will be: a) Acidic (d) 11. Which indicator is best (a) b) Neutral (b) c) Alkaline (c) d) Undefined used for titrations of weak acids with strong bases?