Question

Why ethylenediamine acetic acid is not used for preparation of primary standard solution?

Answer 1

Work in this laboratory on the use of ethylenediamine- tetra-acetic acid as a titrant in volumetric analysis gave rise to the opinion that the dihydrated disodium salt of this acid, the form in which that reagent is generally available commercially, is not a sound primary standard for work of the highest accuracy.A primary standard is a reference chemical used to measure an unknown concentration of another known chemical. It can be used directly when performingtitrations or used to calibrate standard solutions.