How does titration of strong acid strong base differ from titration of weak acid strong base respect to quantity of base required to reach equivalent point?

Answer 1

There are three major differences between strong acid/strong base and weak acid/strong base titrations.

For weak acid/strong base titrations:

1. The weak-acid solution has a higher initial pH. 2. The pH rises more rapidly at the start, but less rapidly near the equivalence point. 3. The pH at the equivalence point does not equal 7.00. (should be >7)

In an acid-base titration, there is a 1:1 acid:base stoichiometry, so the equivalence point is the point where the moles of titrant added equals the moles of substance initially in the solution being titrated. Therefor the strength of the acid or base should not have an affect on the quantity of base required, only on the pH of the equivalence point. The number of moles of titrant and solution will have an effect on the quantity of base required.

Answer 2

In titration of a strong acid with a strong base, the equivalence point is reached with equal amounts of acid and base due to their complete dissociation. However, in titration of a weak acid with a strong base, more base is required to reach the equivalence point because the weak acid does not completely dissociate in solution, necessitating further base to neutralize it.