Question

What do electronegativity values indicate?

Answer 1

Electronegativity is the tendency of a bonded atom to attract shared electrons to itself. The greater the electronegativity, the greater the attraction. Differences in electronegativities between atoms can indicate the type of bond.

Explanation:

Electronegativity differences `(Delta"EN")` between bonded atoms can indicate bond character, i.e. nonpolar covalent, polar covalent, and ionic. Bonds with low `Delta"EN"`, such as `<=0.4` tend to be nonpolar covalent. Bonds with moderate `Delta"EN"`, such as `>=0.5<1.7` tend to be polar covalent. Bonds with a large `Delta"EN"`, such as `>=2.0`.

There is a gap between the `Delta"ENs"` for polar and ionic bonds, which is handled in such a way that if the bonded atoms are nonmetals, the bond is considered polar covalent. If the bond is between a metal and a nonmetal, the bond is considered ionic.

There are differences of opinion within the academic community, mostly about the differences associated with higher values in determining polar and ionic bonds.