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JEE Main202329 Jan 2023Morning ShiftChemistryp Block Elements (Group 13 & 14)Actual

During the borax bead test with CuSO 4 , a blue green colour of the bead was observed in oxidising flame due to the formation of

Options

  1. ACu 3 B 2
  2. BCu
  3. CCu BO 2 2
  4. DCuO

Correct answer

C. Cu BO 2 2

Step-by-step solution

Blue green colour is due to formation of Cu BO 2 2 . Copper gives blue green colour in borax bead test. Reactions which lead to formation of borax bead: CuSO 4 ⟶ Δ CuO + SO 3 CuO + B 2 O 3 → Cu BO 2 2

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