Question

How does the octet rule apply to ionic compounds?

Answer 1

The rule is basically unchanged, except that the pair of shared electrons is usually associated with the more electronegative atom.

In the case of `HF`, the two atoms form a bond by sharing a pair of electrons. The bond has both covalent and ionic character. However, F is much more electronegative than H, so the two shared pair of electrons are both associated with the F atom, and and the ionic character of the bond is sometimes denoted as `H^+F^-`.