Answer:

Volumetric solutions are standardised by the procedures described in general chapter 4.2.2. When a volumetric solution is to be used in an assay in which the end-point is determined by an electrochemical process (for example, amperometry or potentiometry), the solution is standardised by the same procedure.

The composition of the medium in which a volumetric solution is standardised should be the same as that in which it is to be used.