Which statement about polar covalent bonds is true?

• A. They occur when electrons are shared equally
• B. They involve a complete transfer of electrons
• C. They do not involve any electron sharing
• D. They involve unequal sharing of electrons

Answer: (D)

Polar covalent bonds arise when two atoms have different electronegativities, so the electrons in the bond are drawn more toward the more electronegative atom. This unequal sharing creates partial charges on the atoms and gives the bond a dipole, which is why the molecule is polar. A classic example is water, where oxygen pulls electron density toward itself, making O partially negative and H partially positive. This is exactly what the statement describes: unequal sharing of electrons. In contrast, equal sharing would be a nonpolar covalent bond, and a complete transfer of electrons would be an ionic bond.