What is titration?

How a titration works

In a titration, a standard solution of accurately known concentration — the titrant — is delivered from a burette into a measured volume of the sample. As the two react, the chemist watches for the moment the reaction is complete. The equivalence point is where the titrant exactly matches the amount of substance being measured, according to the balanced reaction. Because the reaction follows fixed proportions, the volume of titrant needed reveals the unknown concentration through a simple calculation from the stoichiometry.

Endpoint and indicators

In practice the equivalence point is detected as an observable endpoint, often a sharp colour change produced by an added indicator. In acid–base titrations, indicators such as phenolphthalein change colour over a characteristic pH range, signalling completion.

Other titrations use instruments rather than dyes: a pH meter, a conductivity probe, or a potentiometric electrode can locate the endpoint precisely, which is useful for coloured or complex samples.

Uses in research

Titration is a classic, low-cost method for accurate concentration measurement in chemistry, environmental science, and quality control. Common forms include acid–base, redox, complexometric, and precipitation titrations. Although modern instrumental methods such as spectroscopy and chromatography handle many analyses, titration remains valued for its accuracy and traceability when the titrant is standardised against a certified reference, supporting comparable and reusable measurements.