Final answer:
A polar covalent bond is the result of an uneven distribution of electrons between two distinct atoms, leading to partial charges on the atoms involved.
Step-by-step explanation:
The bond formed between two atoms where the electrons are shared unequally is known as a polar covalent bond. In such a bond, one atom exerts a stronger attraction for the bonding electrons than the other, resulting in an uneven distribution of electron density. This causes one atom to have a partial negative charge while the other has a partial positive charge.
The classic example is the bond in a hydrogen chloride (H-Cl) molecule, where the chlorine atom, being more electronegative, holds the shared electrons closer to itself compared to the hydrogen atom. Consequently, chlorine develops a partial negative charge, and hydrogen gains a partial positive charge, leading to a polar bond. This concept can be applied in understanding many molecules and their interactions, as the presence of polar covalent bonds affects the physical and chemical properties of substances.