-Around 400 BC, Democritus stated that atoms exist but they like an invisible sphere. He said that the atoms can only be identified by quantitative properties; shape, size and motion.

-He called his model the "Greek Model"

-The model explained that all atoms were homogeneous.  

-Democritus discovered the idea of matter, which is the building structure of life.

Image Source:

http://reich-chemistry.wikispaces.com/file/view/demo._atom_model.gif/97847685/demo._atom_model.gif

11/9/2010