From data in Table 16.4, determine 

(a) K_a for C₅H₅NH⁺;

(b) K_b for HCOO^-; 

(c) K_b for C₆H₅O^-.

Table 16.4

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TABLE 16.4 lonization Constants of Some Weak Acids and Weak Bases in Water at 25 °C lonization Constant K Acid Iodic acid Chlorous acid Chloroacetic acid Nitrous acid Hydrofluoric acid Formic acid Benzoic acid Hydrazoic acid Acetic acid Hypochlorous acid Hydrocyanic acid Phenol Hydrogen peroxide Base Diethylamine Ethylamine Ammonia Hydroxylamine Pyridine Aniline lonization Equilibrium HIO3 + H₂O → H3O+ + 103¯ HCIO₂ + H₂O H3O+ + ClO₂ CICH₂COOH + H₂O HNO₂ + H₂O HF + H₂O HCOOH + H,O C6H₂COOH + H₂O HN3 + H₂O CH3COOH + H₂O HOCI + H₂O HCN + H₂O C6H₂OH + H₂O H3O+ + CICH₂COO™ H3O+ + NO₂ H₂O+ + F- H,O+ + HCOO- H3O+ + C6H₂COO™ H₂O + N₂¯ H3O+ + CH3COO- H₂O+ + OCI- H3O+ + CN- H3O+ + C6H₂O H,O,+ H,O = H,O* + HO, H₂O+ (CH3CH₂)₂NH + H₂O CH,CH,NH, + H,O NH3 + H₂O HONH, + H,O C5H₂N + H₂O CH;NH, + H,O Ka 1.6 X 10-1 1.1 X 10-2 = 1.4 x 10-3 7.2 x 10-4 6.6 x 10-4 1.8 x 10-4 6.3 × 10-5 1.9 × 10-5 1.8 X 10-5 2.9 × 10-8 6.2 X 10-10 1.0 × 10-10 1.8 X 10-12 Kb = 1.8 x 10-5 (CH3CH₂)₂NH₂+ + OH-6.9 × 10-4 CH3CH₂NH3+ + OH- 4.3 × 10-4 NH₂+ + OH- HONH3 + + OH- C-H5NH+ + OH- C6H5NH₂+ + OH- 9.1 x 10-9 1.5 × 10-9 7.4 X 10-10 pk pk = a 0.80 1.96 2.85 3.14 3.18 3.74 4.20 4.72 4.74 7.54 9.21 10.00 11.74 pKb 3.16 3.37 4.74 8.04 8.82 9.13 = Acid strength Base strength