What makes the wood of your table, the wool of your sweater, or the
computer you're viewing this from "stick" together? Why doesn't a table
fall apart when you touch it? Bonding of atoms is the foundation of why
things "stick" together.
Key Concepts:
Chemical Bond - a bond is the sharing of electrons.
Covalent Bond - when the shared electrons spend nearly equal amounts of
time on each atom.
Ionic Bond - when the electrons reside on one of the atoms. For instance,
sodium and chlorine come together to form salt, NaCl. The bond formed
between these atoms is ionic, where the actual compound could be written
as Na+Cl-. Here, the sodium atom loses one of its
electrons to the chlorine atom. This electron spends the majority of time
bound to the chlorine atom. The bond between the two atoms forms
essentially because of + - attraction between the positive sodium atom and
the negative chlorine atom.
We know that gases like helium and neon are non reactive. What does it
mean to be non reactive? It means that a gas like helium doesn't have
anything to gain by bonding with another atom. In chemistry, we call this
stability. Atoms bond to other atoms to increase their stability. This
is also called "lowering their energy." The higher the energy of a
molecule or atom, the more unstable it is. So, when oxygen and hydrogen
come together to form water, their stability increases, and the atoms,
tied together as a molecule, are "happier!" So, water, H2O is
formed when oxygen and hydrogen react.
