Chapter 16: Acids and Bases

Transcription

1 1. Which is not a characteristic property of acids? A) neutralizes bases B) turns litmus from blue to red C) reacts with active metals to produce H 2 (g) D) reacts with CO 2 (g) to form carbonates E) All of the above are characteristic properties of acids. 3. In the reaction H 2 CO 3 + H 2 O HCO 3 + H 3 O +, the Brønsted acids are A) H 2 CO 3 and H 2 O. D) H 3 O + and H 2 CO 3. B) HCO 3 and H 2 CO 3. E) H 2 O and HCO 3. C) H 2 O and H 3 O Identify the conjugate base of HPO 4 2 in the reaction HCO 3 + HPO 4 2 H 2 CO 3 + PO 4 3 A) H 2 O B) HCO 3 C) H 2 CO 3 D) PO 4 3 E) None of these. 7. Identify the conjugate base of HCO 3 in the reaction CO HSO 4 HCO SO 4 2 A) HSO 4 B) CO 3 C) OH D) H 3 O + 2 E) SO 4 9. Identify the conjugate base of HClO 3 in the reaction ClO HSO 4 HClO 3 + SO 4 A) ClO 3 B) HSO 4 C) OH D) H 3 O + 2 E) SO Identify the conjugate acid of HCO 3 in the reaction HCO 3 + HPO 4 2 H 2 CO 3 + PO 4 3 A) H 2 O B) HCO 3 C) H 2 CO 3 D) PO 4 3 E) HPO Which one of these statements about strong acids is true? A) All strong acids have H atoms bonded to electronegative oxygen atoms. B) Strong acids are 100% ionized in water. C) The conjugate base of a strong acid is itself a strong base. D) Strong acids are very concentrated acids. E) Strong acids produce solutions with a higher ph than weak acids. Page 288

2 15. What is the ph of an aqueous solution that contains OH ions per liter of solution? A) 5.30 B) 6.06 C) 7.94 D) 8.70 E) The OH concentration in a M Ba(OH) 2 solution is A) M. D) M. B) M. E) M. C) M. 19. The OH concentration in a M Ba(OH) 2 solution is A) M. D) M. B) M. E) M. C) M. 21. Calculate the H + ion concentration in a M Ca(OH) 2 solution. A) M D) M B) M E) M C) M 23. A 0.10 M HF solution is 8.4% ionized. Calculate the H + ion concentration. A) 0.84 M B) 0.12 M C) 0.10 M D) M E) M 25. Consider the weak acid CH 3 COOH (acetic acid). If a M CH 3 COOH solution is 5.2% ionized, determine the [H 3 O + ] concentration at equilibrium. A) 0.25 M B) M C) M D) M E) M 27. Calculate the ph of a carbonated beverage in which the hydrogen ion concentration is M. A) 2.34 B) 3.47 C) 6.01 D) 7.99 E) Calculate the H + ion concentration in lemon juice having a ph of 2.4. A) M B) 250 M C) 0.38 M D) M E) 12 M 31. What is the ph of 10.0 ml of M HCl? A) 0.70 B) 2.70 C) 3.70 D) 5.70 E) 10.0 Page 289

3 33. Calculate the ph of a 0.10 M HCN solution that is % ionized. A) 1.00 B) C) 3.15 D) 5.15 E) Calculate the ph of a M NaOH solution. A) B) 2.17 C) D) 6.71 E) Calculate the ph of a 1.6 M KOH solution. A) 1.60 B) 0.20 C) 0.20 D) E) What is the ph of a M Ca(OH) 2 solution? A) 3.0 B) 11.0 C) 2.7 D) 17.0 E) The ph of tomato juice is about 4.5. Calculate the concentration of hydrogen ions in this juice. A) M B) M C) M D) 4. M E) M 43. The ph of a certain solution is 3.0. How many H + (aq) ions are there in 1.0 L of the solution? A) ions B) 1,000 ions C) ions D) 3 ions E) ions 45. Calculate the hydrogen ion concentration in a solution of iced tea with lemon having a ph of A) M D) M B) M E) M C) M 47. Diet cola drinks have a ph of about 3.0, while milk has a ph of about 7.0. How many times greater is the H 3 O + concentration in diet cola than in milk? A) 2.3 times higher in diet cola than in milk B) 400 times higher in diet cola than in milk C) 0.43 times higher in diet cola than in milk D) 1,000 times higher in diet cola than in milk E) 10,000 times higher in diet cola than in milk Page 290

4 49. The ph of coffee is approximately 5.0. How many times greater is the [H + ] in coffee than in neutral water? A) 200 B) 100 C) 5.0 D) 1.4 E) What is the ph of a solution prepared by mixing 10.0 ml of a strong acid solution with ph = 2.00 and 10.0 ml of a strong acid solution with ph = 6.00? A) 2.0 B) 2.3 C) 4.0 D) 6.0 E) The poh of a solution is Calculate the hydrogen ion concentration in the solution. A) M D) M B) 3.6 M E) M C) M 55. Which one of the following statements is true for a 0.1 M solution of a weak acid HA? A) The concentration of H + is slightly greater than the concentration of A. B) The ph equals 1.0. C) The concentration of H + is exactly equal to the concentration of A. D) The ph is less than 1.0. E) The concentration of H + is slightly less than the concentration of A. 57. Acid strength decreases in the series: strongest HSO 4 > HF > HCN. Which of these species is the weakest base? 2 A) HF B) SO 4 C) F D) CN 59. Acid strength decreases in the series: HCl > HSO 4 > HCN. Which of these species is the strongest base? A) CN 2 B) SO 4 C) HCN D) Cl 61. Which of these acids is the strongest? A) H 2 SO 3 B) H 2 SeO 3 C) H 2 TeO Arrange the acids HOBr, HBrO 3, and HBrO 2 in order of increasing acid strength. A) HOBr < HBrO 3 < HBrO 2 D) HBrO 3 < HOBr < HBrO 2 B) HOBr < HBrO 2 < HBrO 3 E) HBrO 3 < HBrO 2 < HOBr C) HBrO 2 < HOBr < HBrO 3 Page 291

5 65. Arrange the acids H 2 Se, H 2 Te, and H 2 S in order of increasing acid strength. A) H 2 S < H 2 Se < H 2 Te D) H 2 Se < H 2 S < H 2 Te B) H 2 S < H 2 Te < H 2 Se E) H 2 Se < H 2 Te < H 2 S C) H 2 Te < H 2 S < H 2 Se 67. Which one of these net ionic equations represents the reaction of a strong acid with a weak base? A) H + (aq) + OH (aq) H 2 O(aq) B) H + (aq) + CH 3 NH 2 (aq) CH 3 NH + 3 (aq) C) OH (aq) + HCN(aq) H 2 O(aq) + CN (aq) D) + HCN(aq) + CH 3 NH 2 (aq) CH 3 NH 3 (aq)+ CN (aq) 69. Which one of these equations represents the reaction of a weak acid with a weak base? A) H + (aq) + OH (aq) H 2 O(aq) B) H + (aq) + CH 3 NH 2 (aq) CH 3 NH + 3 (aq) C) OH (aq) + HCN(aq) H 2 O(aq) + CN (aq) D) HCN(aq) + CH 3 NH 2 (aq) CH 3 NH + 3 (aq) + CN (aq) 71. Predict the direction in which the equilibrium will lie for the reaction H 2 CO 3 + F HCO 3 + HF. K a1 (H 2 CO 3 ) = ; K a (HF) = A) to the right B) to the left C) in the middle 73. Predict the direction in which the equilibrium will lie for the reaction H 2 SO 3 (aq) + HCO 3 (aq) HSO 3 (aq) + H 2 CO 3 (aq). K a1 (H 2 SO 3 ) = ; K a1 (H 2 CO 3 ) = A) to the right B) to the left C) in the middle 75. Predict the direction in which the equilibrium will lie for the reaction H 3 PO 4 + NO 3 H 2 PO 4 + HNO 3 K a (H 3 PO 4 ) = A) to the right B) to the left C) in the middle 77. Which of the following yields an acidic solution when dissolved in water? A) NO 2 B) LiOH C) K 2 O D) NaCl E) Ca(OH) 2 Page 292

6 79. P 4 O 10 is classified as an acidic oxide because it A) reacts with acids to produce a salt. B) is insoluble in water. C) reacts with water to produce OH. D) gives a solution of phosphoric acid, H 3 PO 4, on dissolving in water. E) can act as a Lewis base by donating electron pairs. 81. Which of these species will act as a Lewis acid? A) NH 3 B) NH 4 + C) H 2 O D) BF 3 E) F 83. Hydrosulfuric acid is a diprotic acid, for which K a1 = and K a2 = Determine the concentration of sulfide ion in a 0.10 M hydrosulfuric solution. A) 0.10 M D) M B) M E) M C) M 85. Calculate the concentration of chromate ion (CrO 2 4 ) in a M solution of chromic acid (H 2 CrO 4 ). [For chromic acid, K a1 = 0.18, K a2 = ] A) M D) M B) M E) 0.21 M C) M 87. For H 3 PO 4, K a1 = , K a2 = , and K a3 = An aqueous solution of NaH 2 PO 4 therefore would be A) neutral. B) basic. C) acidic. 89. An aqueous solution of KCl would be A) neutral. B) basic. C) acidic. 91. Which one of these salts will form a basic solution on dissolving in water? A) NaCl B) KCN C) NaNO 3 D) NH 4 NO 3 E) FeCl What is the ph of a 0.20 M solution of NH 4 Cl? [K b (NH 3 ) = ] A) 3.74 B) 4.98 C) 6.53 D) 9.02 E) Page 293

7 95. Consider the weak bases below and their K b values: C 6 H 7 O K b = C 2 H 5 NH 2 K b = C 5 H 5 N K b = Arrange the conjugate acids of these weak bases in order of increasing acid strength. A) C 5 H 5 NH + < C 6 H 7 OH < C 2 H 5 NH D) C 6 H 7 OH < C 2 H 5 NH + 3 < C 5 H 5 NH + B) C 6 H 7 OH < C 5 H 5 NH + < C 2 H 5 NH E) C 2 H 5 NH + 3 < C 5 H 5 NH + < C 6 H 7 OH C) C 5 H 5 NH + + < C 2 H 5 NH 3 < C 6 H 7 OH 97. Which response gives the products of hydrolysis of KF? A) KOH + HF D) KH + F + OH B) OH + HF E) No hydrolysis occurs. C) KOH + H + + F 99. Which one of these salts will form a basic solution upon dissolving in water? A) NaI B) NaF C) NH 4 NO 3 D) LiBr E) Cr(NO 3 ) Which one of the following salts will form an acidic solution on dissolving in water? A) LiBr B) NaF C) KOH D) FeCl 3 E) NaCN 103. What mass of sodium nitrite must be added to 350. ml of water to give a solution with ph = 8.40? [K a (HNO 2 ) = ] A) 68 g B) g C) g D) 8.3 g E) 24 g 105. What is the ph of a solution prepared by mixing 100. ml of M HCl with 300. ml of M HF? [K a (HF) = ] A) 1.47 B) 1.90 C) 1.30 D) 1.63 E) The equilibrium constant for the reaction C 6 H 5 COOH(aq) + CH 3 COO (aq) C 6 H 5 COO (aq) + CH 3 COOH(aq) is 3.6 at 25 C. If K a for CH 3 COOH is , what is the acid dissociation constant for C 6 H 5 COOH? A) B) C) D) E) Page 294

8 109. For maleic acid, HOOCCH=CHCOOH, K a1 = and K a2 = What is the concentration of maleate ion ( OOCCH=CHCOO ) in a M aqueous solution of maleic acid? A) M D) M B) M E) M C) M 111. What mass of sodium cyanide must be added to 250. ml of water in order to obtain a solution having a ph of 10.50? [K a (HCN) = ] A) 240 g B) g C) g D) 0.94 g E) 0.24 g 113. A tablet of a common over-the-counter drug contains 200. mg of caffeine (C 8 H 10 N 4 O 2 ). What is the ph of the solution resulting from the dissolution of two of these tablets in 225. ml of water? (For caffeine, K b = ) A) 2.76 B) 7.67 C) D) 6.33 E) Which of these lists of molecules is arranged in order of increasing acid strength? A) H 2 S < H 2 O < H 2 Se D) H 2 S < H 2 Se < H 2 O B) H 2 O < H 2 S < H 2 Se E) H 2 O < H 2 Se < H 2 S C) H 2 Se < H 2 O < H 2 S 117. Suppose that ammonia, applied to a field as a fertilizer, is washed into a farm pond containing L of water. If the ph of this pond is found to be 9.81, what volume of liquid ammonia found its way into the pond? [Given: K b (NH 3 ) = ; the density of liquid ammonia is g/cm 3 ] A) 15 L B) 25 L C) 11 L D) 19 L E) 320 L Page 295