Question

How is Cu2+ identified by borax bead test and what are borax bead test? Kindly answer sir/mam.

Answer 1

Borax bead test is used to identify the present metal in given salt or mineral. The chemical formula of borax is Na2B4O7 .10H2O.
To perform the test a small loop is formed at the end of a platinum wire. The loop is cleaned with concentrated hydrochloric acid and dipped in powdered borax, then heated in the flame of a Bunsen burner until the borax melts, forming a bead. The bead is dipped into a tiny amount of the compound to be tested and is reheated in the flame.
Copper gives a blue-green colour under oxidising flame in borax bead test.

Answer 2

$\huge\mathcal\blue{Answer:}$

$\boxed{\red{\texttt{Borax\:bead\:test}}}$

Sodium tetaraborate decahydrate $\boxed{\green{Na_2B_4O_7.10H_2O}}$is called borax

On heating borax first it swells up due to the elimination of the water molecules. On further heating it melts to a liquid which then solidifies to a transparent glassy mass. It contains sodium meta borate and boric acid

$\red{Na_2B_4O_710H_2O}{\rightarrow}\blue{Na_2B_4O_7}{\rightarrow}\pink{2NaBO_2+B_2O_3}$

${B_2O_3}$ combines with meat oxides to form metal metaborates which form coloured beads. This reaction is called " Borax bead test"

$\blue{B_2O_3+CoO}{\rightarrow}\pink{Co(BO_2)_2}$