A chemist is a scientist who researches and experiments with the properties of chemical substances. They measure the effects of chemical compounds in various situations and study inter-chemical reactions. A chemist will usually work as part of a larger research team, and create useful compounds for use in a wide variety of practical applications.
A biochemist is someone who studies the chemical and physical principles of living things and of biological processes such as cell development, growth, and heredity. Most biochemists work on research teams. Research projects are often interdisciplinary, and biochemists frequently work with experts in other fields, such as physics, chemistry, computer science, and engineering.