Law of equivalence - Volumetric analysis

The Law of equivalence is applied in all volumetric estimations. As per to it, the chemical substances react in the ratio of their chemical equivalent masses.

or the gram equivalent of A= gram equivalent of B

or the milli-gram equivalent of  A=  milli-gram equivalent of B

The point at which the amounts of the two reactants are simply equivalent is termed as equivalence point or end point. An auxiliary substance that assists in the common detection of the completion of the titration or equivalence point or end point is known as indicator, that is, substances which go through some easily detectable changes at the equivalence point are utilized as indicators.