Question

How will you identify borate radical?

Answer 1

When boric acid or borate salt is heated with ethyl alcohol in presence of concentrated H₂SO₄, an ester triethyl borate is formed. The Vapour of this ester burns with a green-edged flame and this reaction is used to identify the presence of borate.

$$4\mathrm{H}{\phantom{A}}_3\mathrm{BO}{\phantom{A}}_3+3\mathrm{C}{\phantom{A}}_2\mathrm{H}{\phantom{A}}_5\mathrm{OH}\stackrel{\mathrm{con}\cdot \mathrm{H}{\phantom{A}}_2\mathrm{SO}{\phantom{A}}_4}{\to }\underset{\text{(Triethyl borate)}}{\mathrm{B}(\mathrm{OC}{\phantom{A}}_2\mathrm{H}{\phantom{A}}_5){\phantom{A}}_3}+3\mathrm{H}{\phantom{A}}_2\mathrm{O}$$