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Q.
The principle involved in the classification of basic radicals, is
AMUAMU 2004
Solution:
Basic radicals have been classified into six groups on the basis of the solubility product of their salt with group reagent. The radicals have been grouped in the order of increasing solubility product. This is the reason why $NiCl _{2}$ does not precipitate with Ist group chlorides or $Zn ( OH )_{2}$ does not precipitate with $Al ( OH )_{3}$ in IIIrd group.