Standardtitrant

Standardtitrant, or standard titrant, is a titrant solution whose concentration has been determined with high accuracy. It is used in titration experiments to determine the amount of analyte in a sample by reacting with the analyte under stoichiometric conditions. The reliability of a titration hinges on knowing exactly how much titrant is delivered, which is ensured by standardization against a primary standard.

Preparation and standardization involve titrating a measured quantity of a primary standard with the titrant and calculating the exact molarity of the titrant from the observed endpoint. Primary standards are chosen for their purity, stability, non-hydroscopic nature, and well-defined composition. Regular re-standardization is common to account for drift, evaporation, or changes in solution composition due to storage conditions or temperature.

Storage and handling require appropriate containers, protection from light and moisture when necessary, and labeling with concentration, date of standardization, and expiry. Temperature can affect the titrant’s concentration and viscosity, so measurements are often performed at controlled temperatures or with temperature compensation in the calculation.

Applications of standard titrants are broad, spanning acid-base, redox, complexometric, and precipitation titrations. Common examples include standardized sodium hydroxide solutions for acid-base titrations, standardized hydrochloric acid, and oxidizing or reducing titrants such as potassium permanganate or iron(II) solutions, depending on the reaction. The choice of titrant is dictated by the analyte’s chemistry and the desired stoichiometry.

Quality and traceability are central concerns: a standard titrant should be traceable to national or international standards, with documented certificates of standardization, lot numbers, and measured uncertainties.