The Atomic Theory

Topic Description

Upon completion of this module, you should be able to describe the contributions of these individuals to the development of the structure of the atom: John Dalton, J. J. Thomson, Ernest Rutherford, and James Chadwick. In the early 1800s, English chemist John Dalton proposed that chemical elements are comprised of small particles, termed atoms, that cannot be broken down into smaller particles. This proposition was an early form of atomic theory. Dalton also stated that all atoms of a particular element are identical and that atoms of one element cannot be converted to atoms of a different element through chemical reactions.