R Lang & Associates
About the Atom
Artists' Rendition of the Atom
Periodic Table. Each represents a different kind of atom. When there is more than one atom of its kind, it forms a molecule of the element. The atomic number indicates how many protons (for example, Hydrogen has 1 proton with atomic number 1). The first 98 elements are found in the Earth. The remaining 20, upto number 118, have been synthesized artificially in labs.
History of the Atom. The history of the atom has thought to significantly begin with Dalton's finding of multiple proportions. Thomson later discovered the electron, and Rutherford inferred a nucleus to the atom. Niels Bohr proposed that electrons were in clearly defined quantized orbits. It wasn't until 1932, when the neutron with neutral charge and mass similar to the proton, was discovered by Chadwick.
A completed model of the Atom