Atomic Theory

1. Atomic Theory Brittany Rigsbee 9-19-11

2. Democritus Theory • In 1417 was when Democritus Theory was discover. The atoms in Democritus theory remain the same but move about in space and combine in various ways to form all macroscopic objects. Early atomic theory stated that the characteristics of an object are determined by the shape of its atoms.

3. Dalton • It was in the early 1800s that John Dalton, an observer of weather and discoverer of color blindness among other things, came up with his atomic theory. Less than twenty years ago in the 1780's, Lavoisier ushered in a new chemical era by making carefulmeasurement which allowed the compositions of compounds to be determined with accuracy. 

4. Thomson • Thomson created electrons in 1897. He also was the Noble Prize Winner. His experiments suggested not only that cathode rays were over 1000 times lighter than the hydrogen atom, but also that their mass was the same whatever type of atom they came from.

5. Millikan • Millikan was a experimental physicist. His measurements was to change the electrons to see if it was going to work more effetely.

6. Rutherford • Rutherford discovered the concept of radioactive. He kind of like Thomson but the only thing that Rutherford did he jut wanted to prove it.

7. Chadwick • In 1932 Chadwick discovered neutrons. Because of the lack of electric. He wanted see the likes to the repel and opposite to the attract. By him doing this he got award.

8. Bohr • The Bohr Theory came up in 1913. How the electrons move in the solar system. He also was a Noble Prize Winner. He wanted to contributions to understanding atomic structure.

9. Quantum Mech. Model • This theory was developed in 1925 by Werner Heisenberg. This theory is providing a mathematical description of the waves particle.