Among the following metal carbonyls,the C-O b | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) The $C-O$ bond order in metal carbonyls decreases as the extent of back-bonding from the metal $d$-orbitals to the $\pi^*$ antibonding orbitals of

Vedclass · Accepted Answer

$\left[V(CO)_6\right]^{-}$

Vedclass · Answer

(D) The $C-O$ bond order in metal carbonyls decreases as the extent of back-bonding from the metal $d$-orbitals to the $\pi^*$ antibonding orbitals of $CO$ increases.Back-bonding increases as the electron density on the metal center increases (i.e.,as the negative charge on the complex increases or the oxidation state of the metal decreases).Let us analyze the electron density on the metal center for each complex:$(A)$ $\left[Mn(CO)_6\right]^{+}$: $Mn$ is in $+1$ oxidation state. Total valence electrons $= 7 - 1 + 12 = 18$.$(B)$ $\left[Fe(CO)_5\right]$: $Fe$ is in $0$ oxidation state. Total valence electrons $= 8 + 10 = 18$.$(C)$ $\left[Cr(CO)_6\right]$: $Cr$ is in $0$ oxidation state. Total valence electrons $= 6 + 12 = 18$.$(D)$ $\left[V(CO)_6\right]^{-}$: $V$ is in $-1$ oxidation state. Total valence electrons $= 5 + 1 + 12 = 18$.The metal center with the lowest oxidation state (highest negative charge) has the highest electron density available for back-bonding.Comparing the oxidation states: $Mn(+1) > Cr(0) = Fe(0) > V(-1)$.Since $\left[V(CO)_6\right]^{-}$ has the lowest oxidation state $(-1)$,it has the highest electron density and thus the strongest back-bonding to $CO$,resulting in the lowest $C-O$ bond order.

Among the following metal carbonyls,the $C-O$ bond order is lowest in

Similar Questions

Which of the following compounds is used as an antiknock agent?

Which element does not form a mononuclear carbonyl?

Which of the following is an oxidizing agent?

Which of the following carbonyls will have the strongest $C-O$ bond?

Which of the following is not an organometallic compound?

Vedclass Test Series

Exam Paper Generator

Online Exam Module