foods and everything else, are built from these
primary particles. The modern scientific view
of matter’s invisible innards is more
complicated, but also more precise and
illuminating.
Atoms and Molecules
All matter on earth is a mixture of around 100
pure substances, which we call the elements:
hydrogen, oxygen, nitrogen, carbon, and so
on. An atom is the smallest particle into
which an element can be subdivided without
losing its characteristic properties. Atoms are
very small indeed: several million would fit
into the period at the end of this sentence. All
atoms are made up of smaller “subatomic”
particles, electrons, protons, and neutrons.
The different properties of the elements arise
from the varying combinations of subatomic
particles that make up their atoms, and in
particular their quotas of protons and