Chemistry, a branch of physical science, is the study of the
composition, properties and behavior of matter. Chemistry is
concerned with atoms and their interactions with other atoms,
and particularly with the properties of chemical bonds.
Chemistry is also concerned with the interactions between atoms
(or groups of atoms) and various forms of energy (e.g.
photochemical reactions, changes in phases of matter, separation
of mixtures, properties of polymers, etc.). 17th century  - It
is the study of the Chemists to liberate that unsensual truth
from its fetters in things of sense, for through it the heavenly
powers are persued with subtle understanding....Knowledge is the
sure and undoubted resolution by experiment of all opinions
concerning the truth....Experiment is manifest demonstration of
the truth, and resolution the putting away of doubt. We cannot
be resolved of any doubt save by experiment, and therefore is no
better way to make it than on ourselves. Let us therefore verify
what we have said above conc