Question

What is the colour of borax bead in the basic radical chromium test?

(a) White

(b) Brown white

(c) Green

(d) Blue

I have been asked this question by my college professor while I was bunking the class.

This intriguing question comes from p-Block Elements in division p-Block Elements of Chemistry – Class 11

Answer 1

Correct answer is (c) Green

To explain: Borax bead is used for the detection of coloured basic radicals under the name borax bead test. The action of heat on borax gives Sodium metaborate and boric anhydride which form a Glassy bead and when it reacts with the basic radical, gives out a colour. For chromium, it is green in colour.