CUET · CHEMISTRY · PYQ PAPER 2023
How many \(Cr-O\) bonds in dichromate ions are of the same bond length and are in resonance?
- A 8
- B 6
- C 3
- D 4
Answer & Solution
Correct Answer
(B) 6
Step-by-step Solution
Detailed explanation
The dichromate ion, \(Cr_2O_7^{2-}\), has two \(Cr\) atoms bridged by one oxygen atom. Each \(Cr\) atom is also bonded to three terminal oxygen atoms. Due to resonance, the three terminal \(Cr-O\) bonds on each chromium atom are equivalent. Thus, there are \(3 + 3 = 6\) terminal…
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