The salt formed from a weak acid and a strong base in this titration is:

The salt formed from a weak acid and a strong base in this titration is:

• A. Neutral.
• B. Acidic.
• C. Basic.
• D. Basic due to hydrolysis of the conjugate base A- in water.

Answer: (D)

A salt formed from a weak acid and a strong base is basic because the conjugate base of the weak acid reacts with water. When the salt dissolves, it yields the conjugate base A− and a cation from the strong base that is essentially neutral. The key player is A−: in water it undergoes hydrolysis, pulling a proton from water to form the weak acid HA and hydroxide ions: A− + H2O ⇌ HA + OH−. Since the original acid is weak, its conjugate base is comparatively ready to accept a proton, so the equilibrium lies toward producing OH−, which raises the pH above 7. The result is a basic solution due to this hydrolysis of the conjugate base in water.

A salt formed from a weak acid and a strong base is basic because the conjugate base of the weak acid reacts with water. When the salt dissolves, it yields the conjugate base A− and a cation from the strong base that is essentially neutral. The key player is A−: in water it undergoes hydrolysis, pulling a proton from water to form the weak acid HA and hydroxide ions: A− + H2O ⇌ HA + OH−. Since the original acid is weak, its conjugate base is comparatively ready to accept a proton, so the equilibrium lies toward producing OH−, which raises the pH above 7. The result is a basic solution due to this hydrolysis of the conjugate base in water.