Question

6.5 pts D Question 6 What is the pH of a solution at the equivalence point during the titration of a weak base with a strong acid. Explain. HTML Editor Paragraph BIU A-E-I E x x TT12pt 1

Answer 1

in titration of weak base and strong acid pH at equivalene point is less than 7.

At equivalence point the pH of the solution depends on dissociation of the salt formed in acid base reaction.

The salt of weak base is act as weak acid.

let a strong acid HA and weak base BOH reacts to form salt AB.

Now hydrolysis reaction of the salt BA is

The molecular equation is

BA (aq) + H₂O $\to$   HA (aq) + BOH (aq)

Net ionic equation is

B⁺ (aq) + H₂O  $\to$ H⁺  (aq) + BOH (aq) .

so , the conjugate acid reacts with water to give H⁺ ion , therefore at equivalence point the solution is acidic hence pH < 7.