The Lewis acid strength of BBr_3,BCl_3,and BF | vedclass

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

Question

(C) The given boron trihalides are electron-deficient molecules that act as Lewis acids by accepting an electron pair.The Lewis acid strength is deter

Vedclass · Accepted Answer

$BF_3 < BCl_3 < BBr_3$

Vedclass · Answer

(C) The given boron trihalides are electron-deficient molecules that act as Lewis acids by accepting an electron pair.The Lewis acid strength is determined by the extent of $ppi-ppi$ back-bonding between the halogen atom and the boron atom.In $BF_3$,the $2p-2p$ back-bonding is most effective due to the similar size of the orbitals,which reduces the electron deficiency of the boron atom significantly.As the size of the halogen increases from $F$ to $Cl$ to $Br$,the effectiveness of back-bonding decreases $(2p-2p > 2p-3p > 2p-4p)$.Therefore,the electron deficiency on boron increases in the order $BF_3 < BCl_3 < BBr_3$,making $BBr_3$ the strongest Lewis acid.

The Lewis acid strength of $BBr_3$,$BCl_3$,and $BF_3$ is in the order:

Similar Questions

Write the chemical reaction to prepare inorganic benzene $(B_3N_3H_6)$.

In the structure of diborane $(B_2H_6)$,the number of $2$-centre-$2$-electron $(2c-2e)$ bonds is $X$ and the number of $3$-centre-$2$-electron $(3c-2e)$ bonds is $Y$. The value of $(X+Y)$ is:

In diborane $(B_2H_6)$,the two $H-B-H$ bond angles are nearly

When $BCl_3$ reacts with water,which of the following substances is formed?

In the following reactions:
$3B_2H_6 + 6NH_3 \text{ (excess)} \xrightarrow{\Delta} 2B_3N_3H_6 + 12H_2$
$6NaH + 2BF_3 \xrightarrow{450 \ K} B_2H_6 + 6NaF$
$B_2H_6 + 6H_2O \longrightarrow 2H_3BO_3 + 6H_2$
$X, Y$ and $Z$ are respectively:

Vedclass Test Series

Exam Paper Generator

Online Exam Module