Salts formed by reaction of a strong acid with a weak base are acidic, and salts

Question

Salts formed by reaction of a strong acid with a weak base are acidic, and salts formed by reaction of a weak acid with a strong base are basic. This is due to the equilibrium the conjugate has with its acid or base. For example, sodium bicaronate NaHCO3 contains the conjugate of the weak acid H2CO3. The conjugate will reform the acid through the equilibrium

HCO3?(aq)+H2O(aq)?H2CO3(aq)+HO?(aq)

and, thus, acts as a weak base. A solution of NaHCO3yields a basic solution.

If a salt is derived from a weak acid and a weak base, the pH of the solution depends on the relative acid strength (Ka) of the cation and base strength (Kb) of the anion. If Ka>Kb, the solution of the salt is acidic. If Ka<Kb, it is basic. If Ka? Kb, it is neutral.

Given that

Explanation / Answer

Ka for HCN is 4.9

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.