Final answer:
An ionic bond is created by the transfer of electrons from one atom to another, forming oppositely charged ions, while a covalent bond involves the equal or unequal sharing of electrons between atoms, often resulting in a stronger bond.
Step-by-step explanation:
The fundamental difference between an ionic bond and a covalent bond lies in how electrons are distributed between the atoms involved. An ionic bond is formed when one atom transfers one or more electrons to another atom, typically involving a metal and a nonmetal. This transfer creates a cation (a positively charged ion) and an anion (a negatively charged ion), which are held together by electrostatic forces due to their opposite charges. Examples include sodium chloride (NaCl) where sodium (Na) donates an electron to chlorine (Cl).
In contrast, a covalent bond involves the sharing of electrons between two nonmetal atoms. This sharing can be equal, as in the molecule O2, where two oxygen atoms share electrons equally, or unequally, leading to polar covalent bonds where the shared electrons are closer to one atom than the other, as seen in water (H2O). Covalent bonds are typically stronger than ionic bonds due to the close sharing of electron pairs.