Question

A strong acid is titrated with a weak base. At equivalence point, pH will be
A. ˂7
B. ˃7
C. =0
D. Cannot predict.

Answer 1

Hint: A strong acid is any acid that dissociates completely in solution into ions and gives large numbers of \[{{H}^{+}}\] ions.
A weak base is any base that dissociates incompletely in solution into ions and gives less number of \[O{{H}^{-}}\] ions.

Complete step by step answer:
It is given that a strong acid is titrated with a weak base.
Generally the \[pH\] of an acid is always less than 7.
For strong acids the \[pH\] will be less than 3-4.
Generally the \[pH\] of a base is always greater than 7.
For weak bases the \[pH\] will be 8-9.
In the question it was mentioned that strong acid is going to titrate with weak base, meaning adding weak base to strong acid.
By adding a weak base to strong acid, the \[pH\] solution of the solution is not going to change in a drastic manner.
Because of the high strength the strong acid can retain it \[pH\].
Therefore the \[pH\] of the solution will be less than 7 only.
So, the correct option is A.

Note: Don’t be confused with acid and base. Both are not the same.
An acid is a chemical which releases \[{{H}^{+}}\] ions, when dissolved in water. \[pH\] of an acid is always less than 7.
A base is a chemical which releases \[O{{H}^{-}}\] ions, when dissolved in water. \[pH\] of a base is always greater than 7.