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The Ancient Greeks
Democritus and his friends were thinking about matter. They wondered what would happen if you kept taking something and breaking into smaller and smaller pieces? Would it always be a piece of a tree? Democritus that if you keep breaking it down, you would get to a size that could no longer be broken. -
John Dalton
John Daltom was an English Scientist, that agreed with the Democratius model of the atom However, Dalton said that stuff can be broken into elements, elements are atoms with different masses, and compounds are combinations of elements. -
William Crookes
William Croookes studied the Cathode ray tube, he called the ends of the tubes the Anode and the Cathode. When he placed an object between the ray of green light, and the shadow faced the Anode end. He then knew that the light came from the Cathode, therefore it was called the Cathode Ray Tube. CRT for short. -
JJ Thomson
JJ Thomson was constantly messing around with Cathode Rayrs, These are beams of electrons. By having the beam interact with electic magnetic fields, Thomson was able to determine the mass to charge ratio for an electron.With this charge to mass ratio, he was pretty sure the electron was really reall small. -
The Lord Rutherford of Nelson
Ernest Rutherford thought to himself one day "Hey, I think I will shoot some stuff at atoms." So he did, he shot Alpha particles at some really thin gold foil. Some of them were deflected, which was a huge discovery in science. -
Niels Bohr
The model proposed by Niels Bohr is the one that you will see in a lot of introductory science texts. There are a lot of good ideas on this model, but it is not the one that agrees with all of the current. -
Werner Heisenberg
The key point of the Bohr model that is no longer accpeted in current models of the atom. The electrons, though, are still thought to orbit the nucleus
