During the borax bead test with CuSO4, a blue green colour of the bead was observed in oxidising flame due to the…
p-Block Elements (Class 11) · Class 11 · JEE Main Previous Year Question
During the borax bead test with , a blue green colour of the bead was observed in oxidising flame due to the formation of
- a
- b
Cu
- c✓
- d
CuO
Strategy: Identify the blue-green coloured product formed during the borax bead test with CuSO₄ in an oxidising flame.
Step 1: Borax Bead Test — Chemistry When borax () is heated, it first melts, then loses water and forms a glassy bead of :
Step 2: Reaction with CuSO₄ in Oxidising Flame In the oxidising flame, reacts with to give copper metaborate, which imparts a characteristic blue-green colour:
The blue-green bead is due to (copper metaborate).
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