Bohr worked on the first atomic bomb, the Manhattan project. He also increased peoples knowledge of an atoms structure. http://en.wikipedia.org/wiki/Neils_Bohr
Ernest Rutherford discovered the proton and determined that it had a +1 charge and was located inside of the atom's nucleus. http://www.glafreniere.com/sa_protons.htm
Rutherford disproved the pudding plum model of an atom using the "gold foil experiment" and proved that atoms have a small positively charged nucleus. http://en.wikipedia.org/wiki/Ernest_Rutherford
Stated that all matter is made up of atoms, atoms of a particular element are all the same size, mass and chemical properties. He called this theory the modern atomic theory by experimentation. He believed that atoms can form different compounds and wrongly thought that atoms cannot be created or made smaller. http://en.wikipedia.org/wiki/John_Dalton
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