Method of analysis in which a solution of the substance being determined is treated with a solution of a suitable reagent of exactly known concentration. The reagent is added to the substance until the amount added is equivalent to the amount of substance to be determined. The point of equivalence (end point) in titrimetric analysis is usually determined by a change in colour of an auxiliary reagent (the indicator), but may also be detected by electrical means (potentiometric, conductometric, titrimetry, etc.).