The titration of an acid with a base or of a base with an acid is very convenient method for measuring quantities of the substances in the solution. This process of titration is done by adding a solution of the reagent of known concentration taken in a burette to unknown solution taken in a flask known as titration flask. The solution taken in a burette is called titrant and the other solution taken in the titration flask is called analyte. The titration is continued until the stoichiometric amounts of the two reagents have been mixed. For example:
In a titration of HCl (strong acid) and NaOH (strong base), the reaction which takes place is:-
HCl (aq) + NaOH (aq) —————-> NaCl (aq) + H2O (l)
At equivalence point:
H+ (aq) + OH– (aq) ———–> H2O (l)
There are several points for determining the equivalence point. One such method is by adding indicators to the solution.
