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The green colour produced in the borax bead test of a chromium(III) salt is due to -

Options

  1. AC r B O 2 3
  2. BC r B
  3. CC r 2 B 4 O 7 3
  4. DC r 2 O 3

Correct answer

A. C r B O 2 3

Step-by-step solution

Borax bead test Na 2 B 4 O 7 .10H 2 O  → Δ Na 2 B 4 O 7   → Δ NaBO 2   + B 2 O 3 C r 2 O 3 + B 2 O 3   → Δ G r e e n   c o l o u r e d        C r ( B O 2 ) 3

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