What is the difference between a nonpolar covalent bond and a polar covalent bond?
When atoms share electrons equally a nonpolar covalent bond results. When atoms share electrons unequally a polar covalent bond results. When atoms are equally attractive to electrons they must share the electrons equally and a nonpolar bond is formed. When one atom is more attractive to electrons, the electrons being shared are held closer to that atom causing it to become slightly negative and the other atom to become slightly positive. This is a polar bond.