SOLVED

31) 0.375 g of a monoprotic acid (mm = 245 g/mol) is dissolved in water to produce 25.0 mL of a solution with pH = 3.28. Determine the ionization constant of the acid. A) 8.56 × 10-3 B) 4.5 × 10-6 C) 7.4 × 10-5 D) 4.5 × 10-3 E) 2.3 × 10-2 32) 0.653 g of a monoprotic acid (mm = 157 g/mol) is dissolved in water to produce 50.0 mL of a solution with pH = 2.13. Determine the ionization constant of the acid. A) 7.9 × 10-3 B) 8.9 × 10-2 C) 6.6 × 10-4 D) 3.9 × 10-2 E) 3.6 × 10-6 33) A 0.632 M solution of a monoprotic base has a pH of 11.53. What is the ionization constant of this base? A) 1.8 × 10-5 B) 2.1 × 10-3 C) 1.6 × 10-23 D) 5.0 × 10-12 E) 5.3 × 10-3 34) A 0.214 M solution of a monoprotic base has a pH of 11.48. What is the ionization constant of this base? A) 1.4 × 10-2 B) 4.3 × 10-5 C) 1.5 × 10-11 D) 5.1 × 10-23 E) 2.0 × 10-6 35) A 0.505 g sample of a monoprotic base (mm = 45.09 g/mol) was dissolved in water to produce 100.0 mL of solution with a pH = 11.84. What is the ionization constant of this base? A) 4.3 × 10-5 B) 1.9 × 10-23 C) 4.3 × 10-4 D) 3.4 × 10-1 E) 1.3 × 10-11 36) A 0.0925 g sample of a monoprotic base (mm = 17.03 g/mol) was dissolved in water to produce 100 mL of solution with a pH = 11.00. What is the ionization constant of this base? A) 1.8 × 10-6 B) 1.8 × 10-11 C) 1.8 × 10-21 D) 1.9 × 10-5 E) 1.1 × 10-6 37) Which of the following statements is NOT true? A) In liquid ammonia, the strongest possible base is the NH2- ion. B) Ammonium hydroxide and acetic acid have equal ionization constants in water at 25 °C because of the leveling effect. C) The second ionization constant of a diprotic acid is always smaller than the first ionization constant. D) A Br∅nsted base may be any substance that can act as a proton acceptor. E) Bases neutralize acids to form salts plus water. 38) For which of the following polyprotic acids is the first ionization step approximately 100%? A) H2S B) H2SO3 C) H2CO3 D) H2SO4 E) H3PO4 39) What is the [HPO4-2] of a solution labeled “0.10 M Phosphoric Acid”? [Ka1 = 7.1 × 10-3; Ka2 = 6.3 × 10-8; Ka3 = 4.2 × 10-13] A) 4.2 × 10-13 M B) 6.3 × 10-8 M C) 7.1 × 10-3 M D) 1.6 × 10-9 M E) 1.6 × 10-16 M 40) What is the [AsO43-] for a solution labeled 0.10 M arsenic acid (H3AsO4)? [Ka1 = 6 × 10-3, Ka2 = 1 × 10-7, Ka3 = 3 × 10-12] A) 1 × 10-7 M B) 1 × 10-17 M C) 3 × 10-12 M D) 3 × 10-19 M E) 6 × 10-10 M