31 janv. 1800 av. J.-C. - Dalton

Description:

1766-1844
-Each element is composed of atoms.
-Atoms are neither created or destroyed.
-Atoms can't be subdivided or changed of any other element.
-Atoms of one element differ from mass and other properties from atoms of other elements.
-All atoms of the same element are identical in mass and size.
Atoms of different elements combine in simple whole number ratios.