- When the electronegativity of atoms is similar, an electron pair that they share is equally attracted by both atoms, making this covalent bond non-polar.
- The difference in the electronegativity of two atoms is less than 0.5. However, when two atoms differ in their electronegativity by more than \(0.5\)but up to\(1.7\), an electron pair is closer to the atom with a higher value of electronegativity, so this covalent bond is known as polar.
- Elements placed on the left lower part of the periodic table have the lowest values of electronegativity, while the ones on the right upper portion have the highest values of electronegativity.
A hydrogen atom has an electronegativity of \(2.2,\) which is significantly higher than most metals, so the electron pair that hydrogen shares with a certain metal will be closer to the hydrogen, and its oxidation state would be +1.
However, nonmetals usually have a higher electronegativity than hydrogen, so an electron pair that hydrogen shares with a nonmetal element would be closer to that particular nonmetal,resulting in an oxidation state of hydrogen\( + 1\).
