Question

In borax bead test which compound is formed?

• A. Ortho borate
• B. Meta borate
• C. Double oxide
• D. Tetra borate

Answer 1

Answer: (B)

Meta borate

Answer 2

In borax bead test the coloured meta borates are formed by transition metal salts. $Na_2B_4O_7 . \, 10H_2O \xrightarrow[-10H_2O] {\triangle} Na_2 B_4 O_7$ \hspace30mm $\xrightarrow{\triangle} 2NaBO_2 + B_2O_3$ $B_2O_3 + CuO \longrightarrow Cu(BO_2)_2$ \hspace30mm Cupric m etaborate \hspace30mm (Blue bead)