Final answer:
A nonpolar covalent bond is one in which the electrons are shared equally between two atoms. A polar covalent bond is one in which one atom has a greater attraction for the electrons than the other atom. If this relative attraction is great enough, then the bond is an ionic bond.
Step-by-step explanation:
A nonpolar covalent bond is one in which the electrons are shared equally between two atoms.
A polar covalent bond is one in which one atom has a greater attraction for the electrons than the other atom. If this relative attraction is great enough, then the bond is an ionic bond.