Question
Question: The correct order of M–C p bond and strength in given metal carbonyls is -...
The correct order of M–C p bond and strength in given metal carbonyls is -
A
[Fe(CO)4]2– > [Co(CO)4]– > [Ni(CO)4]
B
[Ni(CO)4] > [Co(CO)4]–> [Fe(CO)4]2–
C
[Fe(CO)4]2– > [Ni(CO4)] > [Co(CO)4]–
D
[Ni(CO)4] > [Co(CO)4]– = [Fe(CO)4]2–
Answer
Fe(CO)<sub>4</sub>2– > Co(CO)<sub>4</sub>– > Ni(CO)<sub>4</sub>
Explanation
Solution
The greater the positive charge on the central metal atom, less readily the metal can donate electron density into the p order of the carbon dioxide ligands to weaken the C–O bonds. Hence more the –ve charge density on metal more the strength of M–C p bond.