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Democritus Develops the Idea of Atoms
Slide in PowerPointDemoctritus pounds up some stuff in his pestle and mortar until the stuff was reduced into smaller and smaller particles which he called atoma--The Greek word for indivisible. -
John Dalton
Slide in PowerPointHe said that everything is made up of smaller spheres that keep bouncing around. He called them atoms. -
Joseph John Thompson
Slide in PowerPointHe discovered that atoms sometimes have smaller negatve particles called electrons. -
Joseph John Thompson
Slide in PowerPointHe discovers that atoms are surrounded by an elastic sphere with electron scattered in it and had a "soup" of positive charge around it, -
Ernest Rutherford
Slide in PowerpointHe did an experiment in which he shot Helium nuclei at a piece of gold foil. Most of them went rght through but some of them bounced off in different directions. -
Niel Bohr
Slide in PowerPointHe added on to Rutherford's experiment and said that the electrion were in orbits.
