History of the Atom Timeline by Alex and Adren

Democritus

400

Democritus thought there were thing were so small they could not be made any smaller or cut any smaller Stuewer, Roger H. "World Book Online Reference Center | Online Reference Book| Online Encyclopedia." World Book. Roger H. Stuewer, 20 Feb. 2015. Web. 20 Feb. 2015.

Democritus

Period: 400 to 400

John Dalton

Feb 25, 1803

Saffman, Mark. "World Book Online Reference Center | Online Reference Book| Online Encyclopedia." World Book. Mark Saffman, 25 Feb. 2015. Web. 25 Feb. 2015. In 1803, a British chemist named John Dalton developed an atomic theory to explain this discovery.

Thomson

Feb 25, 1897

<a href='http://Huffman, Carl A. "World Book Online Reference Center | Online Reference Book| Online Encyclopedia." World Book. Carl A Huffman, 20 Feb. 2015. Web. 20 Feb. 2015.' >Worldbook</a>H e thought atoms had negative charged particles, he used cathode rays that had negative charged particles.

Rutherford

Apr 25, 1911

<a href='http://Bennett, Linda. "What Rutherford Discovered." Rutherford. Linda Bennett, 2012. Web. 23 Feb. 2015.' >Rutherford</a>He discovered the nucleus of the atom, HE used gold foil he thought they would go staight through the foil. The ray deflected went in different direction while some went straight when he concluded they moved.

Niels Bohr

Feb 25, 1913

Bohr suggested that electrons could travel only in a certain set of orbits around the nucleus.

Erwin Schrodinger

Feb 25, 1928

Schrodinger and Heinsberg discovered that you cannot know the exact position and momentum of the electrons.