The Bond dissociation energy of B - F in BF 3 is 646 kJ mol -1 whereas that of C - F in CF 4 is 515 kJ mol -1. The correct reason for higher B - F bond dissociation energy as compared to that of C - F is

Question

The Bond dissociation energy of B - F in BF 3 is 646 kJ mol -1 whereas that of C - F in CF 4 is 515 kJ mol -1. The correct reason for higher B - F bond dissociation energy as compared to that of C - F is (A) Smaller size of B atom as compared to that of C atom (B) Stronger σ bond between B and F in BF3 as Compared to that between C and F in CF4 (C) Lower degree of p π-p π interaction between B and F in BF 3 than that between C and F in CF 4 (D) Significant p π-p π interaction between B and F in BF 3 whereas there is no possibility of such interaction between C and F in CF 4

Tardigrade Admin · Accepted Answer

In BF 3,, B is sp 2 hybridised and has a vacant 2 p-orbital which overlaps laterally with a filled 2 p-orbital of F forming strong p π - p π bond. However in CF 4, C does not have any vacant p-orbitals to undergo p-bonding. Thus BE B - F > BE C - F .

Q. The Bond dissociation energy of $B - F$ in $B F_{3}$ is $646 k J m o l^{- 1}$ whereas that of $C - F$ in $C F_{4}$ is $515 k J m o l^{- 1}$ . The correct reason for higher $B - F$ bond dissociation energy as compared to that of $C - F$ is

Smaller size of B atom as compared to that of C atom

Stronger $σ$ bond between $B$ and $F$ in $B F_{3}$ as Compared to that between C and F in $C F_{4}$

Lower degree of $p π - p π$ interaction between $B$ and $F$ in $B F_{3}$ than that between $C$ and $F$ in $C F_{4}$

Significant $p π - p π$ interaction between $B$ and $F$ in $B F_{3}$ whereas there is no possibility of such interaction between $C$ and $F$ in $C F_{4}$

In $B F_{3},, B$ is $s p^{2}$ hybridised and has a vacant $2 p$ -orbital which overlaps laterally with a filled $2 p$ -orbital of $F$ forming strong $p π - p π$ bond. However in $C F_{4}, C$ does not have any vacant $p$ -orbitals to undergo $p$ -bonding. Thus $B E_{B - F} > B E_{C - F}$ .

Q. The Bond dissociation energy of B−F in BF3​ is 646kJmol−1 whereas that of C−F in CF4​ is 515kJmol−1. The correct reason for higher B−F bond dissociation energy as compared to that of C−F is

Smaller size of B atom as compared to that of C atom

Stronger σ bond between B and F in BF3​ as Compared to that between C and F in CF4​

Lower degree of pπ−pπ interaction between B and F in BF3​ than that between C and F in CF4​

Significant pπ−pπ interaction between B and F in BF3​ whereas there is no possibility of such interaction between C and F in CF4​

In BF3​,,B is sp2 hybridised and has a vacant 2p-orbital which overlaps laterally with a filled 2p-orbital of F forming strong pπ−pπ bond. However in CF4​,C does not have any vacant p-orbitals to undergo p-bonding. Thus BEB−F​>BEC−F​.

Q. The Bond dissociation energy of $B - F$ in $B F_{3}$ is $646 k J m o l^{- 1}$ whereas that of $C - F$ in $C F_{4}$ is $515 k J m o l^{- 1}$ . The correct reason for higher $B - F$ bond dissociation energy as compared to that of $C - F$ is

Stronger $σ$ bond between $B$ and $F$ in $B F_{3}$ as Compared to that between C and F in $C F_{4}$

Lower degree of $p π - p π$ interaction between $B$ and $F$ in $B F_{3}$ than that between $C$ and $F$ in $C F_{4}$

Significant $p π - p π$ interaction between $B$ and $F$ in $B F_{3}$ whereas there is no possibility of such interaction between $C$ and $F$ in $C F_{4}$

In $B F_{3},, B$ is $s p^{2}$ hybridised and has a vacant $2 p$ -orbital which overlaps laterally with a filled $2 p$ -orbital of $F$ forming strong $p π - p π$ bond. However in $C F_{4}, C$ does not have any vacant $p$ -orbitals to undergo $p$ -bonding. Thus $B E_{B - F} > B E_{C - F}$ .