2. By: Taylor Cagle and Chris Clemmer

3. Democritus He proposed ideas for an Atom. He used no experiments. Solely based on his beliefs as an individual chemist. 460 BC - 370 BC

4. Dalton He stated that all atoms of an element were identical, they all had the same mass, and that atoms of each element were different. September. 6 th,1768 - July 27 th,1844 Proposed on 1803

5. Goldstein This chemist discovered the anode ray, also suggested the presence of the proton(and it’s positive charge). He used a gas discharge tube to conduct his theory. September 5 th, 1850 – December 26 th, 1930 Proposed “canal rays” in 1886

6. December 18 th,1856 - August 30 th,1914 Proposed electrons on1897

8. Bohr His ideas were similar to that of Rutherford. His model was the second Planetary model. He found that there too were energy levels. October 7 th, 1885 – November 18 th, 1962 Proposed his atomic model on 1922

9. Schrodinger This chemist is responsible for the founding of wave mechanics, and the architect of quantum mechanics. He demonstrated this with his cat thought experiment. Is this cat dead or alive? According to quantum mechanics this cat is 50% alive and 50% dead. August 12 th, 1887 – January 4 th, 1961 Proposed wave mechanics in 1930

10. Chadwick This chemist James Chadwick was the student of Rutherford. He discovered neutrons when he realized certain pieces were missing. He knew that the atomic number was less then the atomic mass, and that electrons had no mass. October 20 th, 1891 – July 24 th, 1974 Proposed neutrons in 1932

11. BIBLIOGRAPHY my.opera.com/.../archive/monthly/?day=20090825 www.learner.org/.../session4/closer3.html www.mlahanas.de/.../NielsHenrikDavidBohr.html http://dl.clackamas.edu/ch104-04/dalton's.htm#top http://en.wikipedia.org http://nobelprize.org/nobel_prizes/physics/laureates/1933/schrodinger- bio.html http://www.visionlearning.com http://www.suite101.com/content/the-discovery-of-the-neutron-a46060 http://www.vigyanprasar.gov.in/scientists/ESchrodinger.htm http://library.thinkquest.org/15567/bio/schrodinger.html http://www.columbia.edu/itc/chemistry/chem-c2507/navbar/chemhist.html