jan 1, 1932 - James Chadwick
Description:
James Chadwick bombarded beryllium atoms with alpha particles. An unknown radiation was produced. Chadwick interpreted this radiation as being composed of particles with a neutral electrical charge and the approximate mass of a proton. This particle became known as the neutron. With the discovery of the neutron, an adequate model of the atom became available to chemists.Added to timeline:
Date:
jan 1, 1932
Now
~ 94 years ago