They give instructions, keep watch over automated processes, and test samples. They also must record and report on test results. Others are marketing or sales representatives. They sell or provide technical information on chemical products. Chemists often specialize in a subfield.
Analytical chemists study what substances are made of.
Inorganic chemists study compounds that are mainly made of elements other than carbon. Organic chemists study the chemistry of the compounds made of carbon. Physical chemists use math to explain reactions of atoms and molecules. Biochemists work with living systems and are considered life scientists, rather than physical scientists. For more information on biochemists, see the occupational listings for Biologists and Medical Scientists.