Competency #6
Answer and Explanation
Remember that covalent bonds occur between two non-metals. Therefore, the only atoms we need to consider are those in the upper right (pink in the above table) and hydrogen (H), which often behaves as a non-metal.
A polar covalent bond will occur between any two atoms that have substantially different electronegativities. For example, C—F, C—Cl, H—Cl, H—Br. In polar covalent bonds, one atom pulls more strongly on the shared electrons than the other atom. The electronegativity is a measure of how strongly an atom will pull on the electrons.
A non-polar covalent bond will occur between any two atoms that have similar electronegativities. For example, C—I, C—C, H—H, Cl—Cl, H—At. In non-polar covalent bonds, the atoms pull equally or nearly equally on the shared electrons.