Which point of neutralisation reactions do titration indicators help us see?

Titration indicators are used in acid-base titrations to signal the point at which the reaction has been neutralized. This point is known as the equivalence point or the endpoint of the titration.

Here are the steps:

1. A titration starts with a solution of known concentration (the titrant) in a burette. This is typically an acid or a base.

2. The solution in the burette is slowly added to a solution of unknown concentration (the analyte) in a flask. The analyte solution also contains a few drops of a pH-sensitive indicator.

3. As the titrant is added, it reacts with the analyte. If the titrant is an acid, it will react with and neutralize the base in the analyte. If the titrant is a base, it will react with and neutralize the acid in the analyte.

4. The indicator in the analyte solution changes color at a certain pH. This pH is chosen so that it is reached when the amount of titrant added is just enough to completely react with (or neutralize) the analyte. This is the equivalence point of the titration.

5. The color change of the indicator signals that the equivalence point has been reached. This is the point that titration indicators help us see.

6. By knowing the volume of the titrant that was needed to reach the equivalence point, and knowing the concentration of the titrant, the concentration of the analyte can be calculated.