-
100
1 BC (400BC)
-Democritus
-He said that matter is an irriversable decay into another form of matter.
-Around 400BC
-He used common sense by obsering people, trees and other materials.
http://www.livescience.com/9411-strangest-nature.html -
Dalton (1803)
-Dalton
-He discovered that atoms make up elements and elements are a cluster of the same atom
-1803
-He observed weather, the atmosphere and certain gases and he calculated the atomic weights.
http://www.iun.edu/~cpanhd/C101webnotes/composition/dalton.html -
Thomson
-Thomson
-He discovered the electron which he though was surrounded by postive particles.
-1904
-He used the Cathode ray experiment to prove this.
http://en.wikipedia.org/wiki/Plum_pudding_model -
Rutherford
-Rutherford
-He theorized that atoms have their chanrge concentrated in a very small nucleus. Which disproved Thomson's theory.
-1911
-He used the Gold foil experiment to figure this out.
http://en.wikipedia.org/wiki/Ernest_Rutherford -
Bohr
-Bohr
-He discovered that electrons are discrete and revovle in stable orbits around the atomic nucleus.
-1913
-He figured this out by using the Rydberg fourmula.
http://en.wikipedia.org/wiki/Niels_Bohr -
Heisenberg and Schrodinger
-Heisenberg and Schrodinger
-He said that the Uncertainty Principle means that electrons do not travel in neat orbits. Also, all electrons that contain Photons will then change momentum and physics.
-He used the Quantum mechanics to prove this.
http://en.wikipedia.org/wiki/Uncertainty_principle
