What Is Titration?

Titration is the process in which one solution is added to another solution such that it reacts under conditions in which the added volume may be accurately measured. It is used in quantitative analytical chemistry to determine an unknown concentration of an identified analyte. Titrations are most commonly associated with acid-base reactions, but they may involve other types of reactions as well.

Titration is also known as titrimetry or volumetric analysis. The chemical of unknown concentration is called the analyte or titrand. A standard solution of a reagent of known concentration is called the titrant or titrator. The volume of titrant that is reacted (usually to produce a color change) is called the titration volume.

How a Titration Is Performed

A typical titration is set up with an Erlenmeyer flask or beaker containing a precisely known volume of analyte (unknown concentration) and a color-change indicator. A pipette or burette containing a known concentration of titrant is placed above the flask or beaker of an analyte. The starting volume of the pipette or burette is recorded. Titrant is dripped into the analyte and indicator solution until the reaction between titrant and analyte is complete, causing a color change (the endpoint). The final volume of the burette is recorded, so the total volume used can be determined.

The concentration of analyte may then be calculated using the formula:

C_a = C_tV_tM / V_a

Where:

• C_a is the analyte concentration, usually in molarity
• C_t is the titrant concentration, in the same units
• V_t is the volume of titrant, usually in liters
• M is the mole ratio between the analyte and reactant from the balanced chemical equation
• V_a is the volume of an analyte, usually in liters