Endpoint (chemistry)

The equivalence point, or stoichiometric point, of a chemical reaction is the point at which chemically equivalent quantities of bases and acids have been mixed. In other words, the moles of acid are equivalent to the moles of base, according to the equation (this does not necessarily imply a 1:1 molar ratio of acid:base, merely that the ratio is the same as in the equation). It can be found by means of an indicator, for example phenolphthalein or methyl orange.

The endpoint (related to, but not the same as the equivalence point) refers to the point at which the indicator changes colour in a colourimetric titration.

Different methods to determine the equivalence point include:

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