Which gives blue color in borax bead test? a. Copper b. Cobalt c. Chromium d. None of these

Which gives blue color in borax bead test? a. Copper b. Cobalt c. Chromium d. None of these

Explanation

In the borax bead test, cobalt ions (Co²+) react with borax to form cobalt metaborate (Co(BO2)2), which produces a distinct blue color.