JEE Advanced · Chemistry · 31. Practical Chemistry
The green colour produced in the borax bead test of a chromium(III) salt is due to -
- A
- B
- C
- D
Answer & Solution
Correct Answer
(A)
Step-by-step Solution
Detailed explanation
Borax bead test
\(Na _2 B_4 O _7 \cdot 10 H _2 O \xrightarrow{\Delta} \underset{C r\left(B O_2\right)_3}{ Na _2 B_4 O _7} \xrightarrow{\Delta} NaBO _2\) \(+~ B _2 O _3\)
\(Cr _2 O _3+ B _2 O _3 \xrightarrow{\Delta}_{\text {Green coloured }}\)
\(Na _2 B_4 O _7 \cdot 10 H _2 O \xrightarrow{\Delta} \underset{C r\left(B O_2\right)_3}{ Na _2 B_4 O _7} \xrightarrow{\Delta} NaBO _2\) \(+~ B _2 O _3\)
\(Cr _2 O _3+ B _2 O _3 \xrightarrow{\Delta}_{\text {Green coloured }}\)
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