titrables

Titrables refers to substances or functional groups that can be quantified by titration with a standard reagent. In chemistry and related disciplines, a titratable quantity is determined by measuring the amount of reagent required to reach a defined endpoint, such as a specified pH or neutralization point. The term is commonly encountered in discussions of titratable acidity and in analyses of foods, beverages, soils, polymers, and biomolecules where acid–base groups are present.

In a titration, a solution containing the titratable species is gradually reacted with a titrant of known concentration. The stoichiometry of the reaction determines how many moles of titratable protons or base equivalents are present. The endpoint is chosen to reflect the chemistry of the reaction, which may be a specific pH reached with an indicator or the true equivalence point determined by measurement methods such as pH, potentiometry, or color change.

Common contexts include titratable acidity in foods and drinks, where total acidity is reported as titratable acidity, and environmental or industrial chemistry, where alkalinity or acidity is quantified by titration. In biochemistry and polymer science, titratable groups refer to ionizable functional groups such as carboxyl (COOH), phosphate, phenolic, or amine groups, whose protonation state changes with pH and can be quantified by titration to assign charge or capacity.

Limitations include dependence on the chosen endpoint, buffering effects, and the assumption of complete reaction with the titrant. The term titratable is field-dependent; while widely used in analytical contexts, it may be replaced by more specific descriptors such as titratable acidity, titratable capacity, or the capacity of ionizable groups depending on the application.