Silicon has $4$ electrons in the outermost orbit. In forming the bonds,

On decreasing the internuclear distance below the optimum distance (where potential energy is minimum),there is a steep increase in potential energy due to:

Multiple covalent bonds exist in a molecule of

The bond between two identical non-metal atoms has a pair of electrons:

The $B-F$ bond dissociation energy in $BF_3$ is $646 \ kJ \ mol^{-1}$,whereas the $C-F$ bond dissociation energy in $CF_4$ is $515 \ kJ \ mol^{-1}$. Which of the following is the correct reason for the $B-F$ bond dissociation energy being higher than the $C-F$ bond dissociation energy?

Which set contains only covalently bonded molecules?