# Ka, Kb and percent ionization: Practice

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### and percent ionization: Practice

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Determine the K a of a weak acid if a 0.300 M solution has a pH of 1.94. What is K b for N 2 H 4 (hydrazine) if a 0.500 M solution has the following concentrations at equilibrium? [N 2 H 4 ] = 0.499 M, [OH ] = 1.23 x 10 -3 M, [N 2 H 5 + ] = 1.23 x 10 -3 A solution of 1.00 M HA in water ionizes 2.00 %. Find K a . A 0.250 M solution of a weak acid is 1.75 % ionized. Determine the pH and K a of this solution. 5.

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What is more acidic, a solution 0.100 M boric acid or a 0.100 M solution of nitrous acid? (see data booklet) C 5 H 5 N is a weak base. A 0.125M solution of this base has a pH of 9.10. Find the K b . 7.

Benzoic acid (C 6 H 5 COOH) is a weak acid. If K a of benzoic acid is 6.46 x 10 -5 then 8.

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find: a) the pH of a 0.0125 M solutionb) the % ionization of this solution What is the percent ionization in 0.0200 M HClO? K a = 3.16 x 10 -8 What is the ethanoate ion concentration in a 0.0178 M solution of ethanoic acid? 10.

What would be the hydrogen ion concentration in a 0.884 M solution of hydrocyanic acid? 11.

The ionization constant of a weak acid is 5.50 x 10 -5 . Find the percent ionization of a 0.0150M solution of the acid. 12.

Ammonia, NH 3 , is a weak base. Find the pH of a 0.150M solution of this base.