Introduction #
Living things are made up of atoms, but in most cases, those atoms aren’t just floating around individually. Instead, they’re usually interacting with other atoms (or groups of atoms).
For instance, atoms might be connected by strong bonds and organized into molecules or crystals. Or they might form temporary, weak bonds with other atoms that they bump into or brush up against. Both the strong bonds that hold molecules together and the weaker bonds that create temporary connections are essential to the chemistry of our bodies, and to the existence of life itself.
Why form chemical bonds? The basic answer is that atoms are trying to reach the most stable state that they can. Many atoms become stable when their valence shell (the last orbit of electrons) is filled with electrons (by having eight valence electrons). If atoms don’t have this stability, they will want to reach it by gaining, losing, or sharing electrons via bonds.
