Question

Can someone give me an example of a electronegativity

Answer 1

A water molecule is non-polar, this is due to a significant difference in the electronegativity values of hydrogen and oxygen ie. σ(H)≈2.20 whereas σ(O)≈3.44
The fact that oxygen is more electronegative than hydrogen means oxygen has a greater potential to take electrons from another atom than hydrogen does.

Answer 2

LiI is more covalent than LiF due to the higher electronegativity of F which pulls the electron density towards itself which makes it less covalent.