Atomic History Timeline

John Dalton's Atomic Theory- atoms can be rearranged chemically and combined to form compounds.

J.J Thomson discovers the electron using the Cathode Ray Tube Experiment

J.J Thomson's Plum Pudding Model suggests that an atom is a ball of positive energy with electrons floating in it

Antoine Lavoisier formulates the Law of Conservation of Mass- the mass of an object remains constant even if the matter changes form or chemically reacts to create a new product.

Erwin Schrodinger's Electron Cloud Model developed through Bohr's work and mathematical equations

Robert Millikan's Oil Drop Experiment is developed through his apparatus and his equation 1.602 x 10^-19

James Chadwick proved the existence of neutrons through research and the assistance of Rutherford

Neils Bohr's Planetary Model is published through the study of the hydrogen atom's electron orbit

Ernest Rutherford's Gold Foil Experiment proves the existence of the nucleus and that most of the atom is empty space. Becomes the Rutherford Model.

Democritus studied atoms and was the first person to propose their existence