# Is it possible for the equivalence point of a titration to not be at pH 7?

Mar 4, 2017

Yes, in fact, it most often is not.

#### Explanation:

Besides the trivial examples of non-acid-base titrations, the equivalence point of an acid-base titration is the point where there is only the salt and water in solution, therefore its $p H$ is simply the pH of the salt.

When it's a strong acid - strong base titration such as

$N a O H + H C l \rightarrow N a C l + {H}_{2} O$
(Sodium Hydroxide - Hydrochloric acid titration)

The remaining salt is made of an extremely weak acid ($N {a}^{+}$) and an extremely weak base ($C {l}^{-}$), neither of which is strong enough to change the pH of water which is $7.00$

However, if we do a strong acid - weak base or strong base - weak acid titration, the remaining salt can change the pH. For example:

$N a O H + C {H}_{3} C O O H \rightarrow C {H}_{3} C O O N a + {H}_{2} O$
(Sodium Hydroxide - Acetic acid titration, used - for example - to analyze vinegar)

The pH of sodium acetate will only be 7 in minute enough quantities.