Question
The bond dissociation energy of $$B - F$$ in $$B{F_3}$$ is $$646\,kJ\,mo{l^{ - 1}}$$ whereas that of $$C - F$$ in $$C{F_4}$$ is $$515\,kJ\,mo{l^{ - 1}}.$$ The correct reason for higher$$B-F$$ bond dissociation energy as compared to that of $$C - F$$ bond is
A.
stronger $$\sigma $$ bond between $$B$$ and $$F$$ in $$B{F_3}$$ as compared to that between $$C$$ and $$F$$ in $$C{F_4}$$
B.
significant $$p\pi - p\pi $$ interaction between $$B$$ and $$F$$ in $$B{F_3}$$ whereas there is no possibility of such interaction between $$C$$ and $$F$$ in $$C{F_4}$$
C.
lower degree of $$p\pi - p\pi $$ interaction between $$B$$ and $$F$$ in $$B{F_3}$$ than that between $$C$$ and $$F$$ in $$C{F_4}$$
D.
smaller size of $$B$$ - atom as compared to that of $$C$$ - atom.
Answer :
significant $$p\pi - p\pi $$ interaction between $$B$$ and $$F$$ in $$B{F_3}$$ whereas there is no possibility of such interaction between $$C$$ and $$F$$ in $$C{F_4}$$