JEE Mains · Chemistry · STD 11 -p-Block elements - I
When borax is heated with \(CoO\) on a platinum loop, blue coloured bead formed is largely due to
- A \(B _{2} O _{3}\)
- B \(Co \left( BO _{2}\right)_{2}\)
- C \(CoB _{4} O _{7}\)
- D \(Co [ B _{4} O _{5}( OH )_{4}]\)
Answer & Solution
Correct Answer
(B) \(Co \left( BO _{2}\right)_{2}\)
Step-by-step Solution
Detailed explanation
\(Na _{2} B _{4} O _{7} \cdot 10 H _{2} O \stackrel{\Delta}{\longrightarrow} Na _{2} B _{4} O _{7}+10 H _{2} O\) \(Na _{2} B _{4} O _{7} \stackrel{\Delta}{\longrightarrow} 2 NaBO _{2} \text { (sodium meta borate) }+ B _{2} O _{3}\)…
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