A polar covalent bond occurs when two atoms do what with electrons?

A polar covalent bond occurs when two atoms share electrons unequally. This phenomenon arises when there is a difference in electronegativity between the two atoms involved in the bond. Electronegativity is the ability of an atom to attract electrons; when one atom has a higher electronegativity than the other, it pulls the shared electrons closer to itself. This unequal sharing results in a partial positive charge on one atom and a partial negative charge on the other, leading to the polarity of the bond.

In contrast, transferring electrons completely would create ionic bonds, where one atom loses electrons entirely and another atom gains them. Sharing electrons equally, as seen in nonpolar covalent bonds, occurs between atoms with similar electronegativities, leading to an even distribution of charge. The idea of one atom absorbing electrons entirely does not correspond to how bonding works in covalent interactions. Thus, the correct understanding of a polar covalent bond identifies the key aspect of unequal electron sharing.