Practice!

Sample Problem

Using the titration curve shown, which letter represents the equivalence point?

A

B

C

D

E

Given that phenolphthalein is an indicator with a pH transition range of 8.3 – 10.0, would using it be a good method in determining the endpoint of the titration?

Yes

No

Solution

The equivalence point is the point at which the base completely neutralizes all of the acid. This occurs at the steepest part of the graph and is then represented by C. The equivalence point has a pH of around 7, so phenolphthalein would be a good indicator for the endpoint.