electrons. Hydrogen atoms contain one proton
and one electron; oxygen carries 8 of each,
and iron 26.
When two or more atoms bond together,
which they do by sharing electrons with each
other, they form a molecule (from the Latin
for “mass,” “bulk”). The molecule is to a
chemical compound what the atom is to an
element: the smallest unit that retains the
properties of the original material. Most
matter on earth, including food, is a mixture
of different chemical compounds.
Protons and Electrons Carry Positive and
Negative Electrical Charges There’s one
primary driving force behind all the chemical
activity that makes life and cooking possible,
and that’s the electrical attraction between
protons and electrons. Protons carry a positive
electrical charge, and electrons an exactly
balancing negative charge. (The neutral
neutron carries no charge.) Opposite electrical