-
300
Aristotle (B.C.)
-was Philosopher/Greek Philosopher
-student of Plato
-he added four basic elements: fire,earth,air,water adding one more element called "Aether"
-he studies in physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, zoology
Http://timelineoftheatom.blogspot.com/p/2.html -
400
Democritus (400 B.C.)
-Democritus discovered the first atom in 400 B.C.
-Claimed that everything is made up of atoms.
-His atom is an inert solid that interacts with other atoms mechanically
-Some people consider him to be father of modern science
-Atom always in motion
-Democritus said atom are indestructible
-Using analogies from our sense ,Democritus gave an image of an atom that distinguished them from each other
Http://www.universetoday.com/60058/democritus-atom/ -
Daton
-He discovered certain gases can only be combined in certain proportions.
-He created the Law of Constant Compostion also called Law of Definite Proportions.
-He divided Atomic Theory into five parts: Pure Element, -----Atom , Atomic weight, Chemical compound, and Chemical Reaction
-Believe element are made up of tiny particles call atom Http://www.universetoday.com/56637/atom-model/ -
Thomson
-This model of the atom was a sphere of positive matter in which electrons are positioned by electrostatic forces.
-Thought electrons and proton are uniformly mixed throughtout atom
-The model was called " Plum Pudding Model"
-He used the Cathode Ray Tube experiment
-He discover electrons
Tomson video -
Rutherford
-Components of atom
-Consist of subatomic particles called proton and electrons
-Rutherford tested Thompson theory by devising his "gold foil" experiment
-Atom has a nucleus
-Rutherford said Thompson's model was correct
- He said put all proton in the nucleus and the electrons orbits the nucleus like the planets orbits the sun
Http://www.iun.edu/~cpanhd/C101webnotes/modern-atomic-theory/rutherford-model.html -
Bohr
Bohr applies quantum theory to Rutherford's atom structure
-Electron cloud model
-Bohr went to England to study with J.J Thompson
-1912 Bohr joined Rutherford
-Bohr earned his PHD in Denmark with a dissertation on electron theory of metals
-Bohr's theory that electrons existed in set orbit around the nucleus was the key to the Periodic repetition of properties of the element
Http://www.pbs.org/wgbh/aso/databank/entries/dp13at. -
Schrodinger / Heisenberg
-Used math
-Schrodinger Equation received a Nobel Prize in Physic in 1933
-Schrodinger Equation is the method he used
-Schrodinger Equation: wave equation of non relativistic quantum mechanics
-The model depicts the floating motion of the electrons, rather then them having a set path of travel
-Schrodinger determined the probiltity location of electrons in atom
- According to Schrodinger, electrons stuck in their orbits would set uo " standing waves"
-Quantum Mechanical model
Http://timelineofth
