Question

With $MnO$, colour of the bead in sodium carbonate-bead test is:

• A. pink
• B. black
• C. yellow
• D. green

Answer 1

The correct option is D green

In a borax bead test, the metal oxides fuse with $B_2{O}_3$ in the borax bead to produce the metaborates.
Oxides of manganese fuse with microcosmic salt in the oxidation flame, to a clear brownish-violet bead, which appears reddish-violet while cooling. This bead does not become opaque when overcharged with manganese.
The oxides of manganese fuse with carbonate of soda upon platinum foil or wire, to a clear green bead, which appears bluish-green and partially opaque when cold.