What is the difference between ionic and covalent bonds?
Ionic bonds form when one atom transfers electrons to another atom, creating oppositely charged ions that attract each other. Covalent bonds form when two atoms share electrons between them.
Steps
In ionic bonding, a metal atom gives up one or more electrons to a nonmetal atom, creating a positively charged ion (cation) and a negatively charged ion (anion).
These oppositely charged ions are held together by electrostatic attraction, forming an ionic compound like table salt.
In covalent bonding, two nonmetal atoms share one or more pairs of electrons so both atoms can fill their outer electron shells.
The shared electrons are attracted to the nuclei of both atoms, holding them together in a molecule.
Ionic compounds typically form crystalline solids with high melting points, while covalent compounds often form molecules that can be gases, liquids, or solids with lower melting points.
Worked example
Sodium chloride (NaCl) is ionic: sodium loses one electron to become Na+, and chlorine gains that electron to become Cl-, then they attract. Water (H2O) is covalent: each hydrogen atom shares one electron with the oxygen atom, so oxygen gets a full outer shell and each hydrogen gets two electrons.
Remember
Ionic bonds involve transferring electrons between a metal and nonmetal, while covalent bonds involve sharing electrons between nonmetals.