Basic Chemistry Copyright © 2011 Pearson Education, Inc. 1 Chapter 14 Acids and Bases 14.9 Acid-Base Properties of Salt Solutions

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 2 Salts That Form Neutral Solutions A salt solution containing the ions of a strong acid and a strong base forms a neutral solution does not produce or attract H + from water Example: KNO 3 forms a neutral solution because it contains a cation (K + ) from a strong base (KOH) and an anion (NO 3  ) from a strong acid (HNO 3 ).

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 3 Salts That Form Basic Solutions A salt solution containing ions of a weak acid and strong base forms a basic solution has an anion of the weak acid that attracts H + from water Example: KHCO 3 forms a basic solution because its anion forms a weak acid (H 2 CO 3 ), but its cation is from strong base (KOH). HCO 3  (aq) + H 2 O(l) H 2 CO 3 (aq) + OH  (aq) Anion of Forms Solution is basic weak acid weak acid

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 4 Salts That Form Acidic Solutions A salt solution containing ions of a strong acid and a weak base forms an acidic solution has a cation of the weak base that produces H + in water Example: NH 4 Cl forms an acidic solution because it has the cation of a weak base (NH 3 ) and an anion of the strong acid (HCl) NH 4 + (aq) + H 2 O(aq) NH 3 (aq) + H 3 O + (aq) Cation of Forms a Solution is acidic weak base weak base

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 5 Cations and Anions of Salts for Neutral, Basic, and Acidic Solutions

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 6 Acid-Base Properties of Salt Solutions

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 7 Learning Check Predict whether a solution of each salt will be (A) acidic, (B) basic, or (N) neutral. 1. Li 2 S (aq) 2. Mg(NO 3 ) 2 (aq) 3. NH 4 Br (aq)

Basic Chemistry Copyright © 2011 Pearson Education, Inc. 8 Solution 1. Li 2 S(aq) (B) basic; S 2 , a cation of a weak base, reacts with H 2 O to produce HS  and OH  ; Li +, a cation of a strong base, does not interact with water. 2. Mg(NO 3 ) 2 (aq) (N) neutral; Mg 2+, a cation of a strong base, and NO 3 , an anion of a strong acid, do not interact with water. 3. NH 4 Br(aq) (A) acidic; NH 4 +, a cation of a weak base, reacts with H 2 O to produce H 3 O + ; Br , an anion of a strong acid, does not interact with water.