Q17 / 90 · JEE Main 2023 (29 Jan Shift 1) · Chemistry

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

A
${Cu}_{3} B_{2}$
B
$Cu$
Correct answer
C
$Cu {({BO}_{2})}_{2}$
D
$CuO$

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:

${CuSO}_{4} \overset{Δ}{⟶} CuO + {SO}_{3}$

$CuO + B_{2} O_{3} \to Cu {({BO}_{2})}_{2}$

Hence, the correct answer is option: 'C'.

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During the borax bead test with CuSO4, a blue green colour of the bead was observed in oxidising flame due to the formation of

Solution

Relevant Questions

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