Titration

Titration Process

Titration is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of a known reactant. Because volume measurements play a key role in titration, it is also known as volumetric analysis. A reagent, called the titrant or titrator, of a known concentration (a standard solution) and volume is used to react with a solution of the analyte or titrant, whose concentration is not known. Using a calibrated burette orchemistry pipetting syringe to add the titrant, it is possible to determine the exact amount that has been consumed when the endpoint is reached.

Acid-Base Titration

An acid-base titration is the determination of the concentration of an acid or base by exactly neutralizing the acid/base with an acid or base of known concentration. This allows for quantitative analysis of the concentration of an unknown acid or base solution. It makes use of the neutralization reaction that occurs between acids and bases and the knowledge of how acids and bases will react if their formulas are known.

The Equivalence Point And End Point Of A Titration

The equivalence point, or stoichiometric point, of a chemical reaction occurs during a chemical titration when the amount of titrant added is stoichiometrically equal to the amount of analyte present in the sample: the smallest amount of titrant that is sufficient to fully neutralize or react with the analyte. In some cases there are multiple equivalence points which are multiples of the first equivalent point, such as in the titration of a diprotic acid.

The end point (similar, but not the same as the equivalence point) refers to the point at which the indicator changes color in a colorimetric titration.

In an acid-base titration, a suitable indicator must be chosen so that the end point coincides with the equivalence point of the two reacting solutions. In order to achieve this, the indicator should change colour sharply at the equivalence...