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Chemistry · PYQ NEET UG 2016(1)
हिन्दीWhich of the following has the longest C - O bond length? (Free C - O bond length in CO is \( 1.128\text{ \AA} \))
Correct answer · Option 1
\( [\text{Fe}(\text{CO})_4]^{2-} \)
Explanation
Greater negative charge on the metal complex increases back-bonding into the \( \pi^* \) orbitals of CO, weakening and lengthening the C-O bond. Thus, \( [\text{Fe}(\text{CO})_4]^{2-} \) has the longest C-O bond.
