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Assertion : C - O bond in metal carbonyl...

Assertion : C - O bond in metal carbonyl is long.
Reason : There is delocalisation of electrons from filled d orbitals into the empty orbitals on the CO ligands.

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reasonb is false

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion and reason statements provided. ### Step 1: Understand the Assertion The assertion states that the C-O bond in metal carbonyl is long. In coordination chemistry, the length of a bond can be influenced by factors such as the nature of the bonding and the presence of back-donation. In metal carbonyl complexes, the C-O bond length can be affected by the interaction between the metal and the CO ligand. **Hint:** Consider how the nature of bonding in metal carbonyls affects bond lengths. ### Step 2: Understand the Reason The reason states that there is delocalization of electrons from filled d orbitals of the metal into the empty orbitals of the CO ligands. This phenomenon is known as back-bonding or synergic bonding. In metal carbonyls, the metal donates electron density to the π* (pi-star) orbitals of CO, which stabilizes the bond and can lead to a longer C-O bond. **Hint:** Think about how electron donation from the metal affects the bond strength and length. ### Step 3: Analyze the Relationship Between Assertion and Reason Both the assertion and reason are related. The assertion about the C-O bond being long is supported by the reason that explains the delocalization of electrons and back-bonding. The back-bonding weakens the C-O bond due to the increased electron density on the CO ligand, leading to a longer bond. **Hint:** Consider how the weakening of a bond can lead to an increase in bond length. ### Step 4: Conclusion Both statements are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason supports the assertion. **Final Answer:** Both the assertion and reason are true, and the reason is a correct explanation of the assertion.
To solve the question, we need to analyze the assertion and reason statements provided. ### Step 1: Understand the Assertion The assertion states that the C-O bond in metal carbonyl is long. In coordination chemistry, the length of a bond can be influenced by factors such as the nature of the bonding and the presence of back-donation. In metal carbonyl complexes, the C-O bond length can be affected by the interaction between the metal and the CO ligand. **Hint:** Consider how the nature of bonding in metal carbonyls affects bond lengths. ### Step 2: Understand the Reason ...
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