The Atomic Models!

This post will explain: how does the atomic models have beign modified and changed with the years, all thanks to the scientists that study them.

• Democritus: In 400 B.C. he thought that matter couldn't be infinitely divided.   
• John Dalton: In 1800, he based in his experiments, not only in his own reason and proposed a modern atomic model. It stated that:
• All matter is made of atoms.
• Atoms of an element are identical
• Atoms are able to join and form a compound.
• Atoms can be rearranged by reactions.
• He also stated the law of conservation of matter, which established that "matter couldn't be created nor distroyed, and he also made the law of constant composition.
• Joseph John: he was born in 1856, he was a british physicist that discovered the electrons, isotopes and the invention of the mass spectrometer.
• Thomson Ernest Rutherford: He was burn in 1871, he discovered a noble gas, he stated that atoms are mostly "empty space", and that negative electrons orbit a positive nucleus, he also researched the properties of the radium emanation.
• Niels Bohr: He was born in 1885, he made the Bohr's model, which established how did electrons orbit the shell, how did the electrons could bump to a higher shell, and the two types of spectra.  
• Werner Heisenberg: He was born in 1901, he studied the quantum mechanics. He also stated the principle of uncertainty.

This is just a summary of the important scientist that studied and discovered important aspects of matter and atoms.

http://www.chalkbored.com/lessons/chemistry-11/atomic-models-handout.pdf