What is the difference between a covalent bond and an ionic bond?

Covalent bonding occurs when two atoms share one or more pairs of electrons, allowing each atom to attain a stable electron configuration. This type of bond typically forms between nonmetals, where the shared electrons enable both atoms to achieve full outer shells, resulting in a stable molecule. An example of a covalent bond is the bond between two hydrogen atoms in H2.

Ionic bonding is the electrostatic attraction between positively charged ions (cations) and negatively charged ions (anions). This bond forms when one atom donates electrons to another, resulting in the formation of charged ions. A common example is sodium chloride (NaCl), where sodium donates an electron to chlorine, creating Na+ and Cl- ions that attract each other.

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. In covalent bonds, atoms with similar electronegativities share electrons equally, while in ionic bonds, a significant difference in electronegativity leads to the complete transfer of electrons from one atom to another. Understanding electronegativity helps predict the type of bond that will form between two elements.