Theory:
1. First to associate the ancient idea of atoms with stoichiometry
2. That a given compound always contains the same proportions (by mass) of the element
3. *Law of Constant Composition*
John Dalton
Theory:
1. Atom is breakable
2. Cathode rars are negatively charged particles
3. Particles are constituents of the atom
4. Atom's structure has electrons suspended in a positively charged electric field
J. J. Thomson
Theory:
1. Atom mostly empty space
2. Atom contains a dense particle that was small in volume, compated to the atom, but large in mass
3. This dense particle was positively charged
Rutherford
Dalton's Atomic Theory
1. Elements are made of tiny particles called atoms.
2. Atoms of one element can combine with atoms of other elements to form compounds