JEE MAIN - Chemistry (2006 - No. 19)
In Fe(CO)5, the Fe – C bond possesses :
π-character only
both $$\sigma$$ and π characters
ionic character
$$\sigma$$-character
Paliwanag
Due to some back-bonding by side-wise overlapping of between $$d$$-orbitals of metal and $$p$$-orbital of carbon, the $$Fe-C$$ bond in $$Fe{\left( {CO} \right)_5}$$ has both $$\sigma $$ and $$\pi $$ character.