Separations Based on Complexation Reactions Masking

One of the most widely used techniques for preventing an interference is to bind the interferent as a soluble complex, preventing it from interfering in the analyte s determination. This process is known as masking. Technically, masking is not a separation 

A pseudo-separation method in which a species is prevented from participating in a chemical reaction by binding it with a masking agent in an unreactive complex. 

The reagent used to bind the species to be masked in an unreactive complex. 

Source Adapted from Meites, L. Handbook of Analytical Chemistry, McGraw-Hill New York, 1963. 

Suggest a masking agent for the analysis of Al in the presence of Fe. Repeat for the analysis of Fe when Al is an interferent. 

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