-
First person to think of the atom.
Though atom was a solid sphere. -
Proposed everything was made from fire, air, water, and earth instead of atoms.
-
Believed that there was little pieces of mass that were "swimming' everywhere.
-
- all matter is comosed of atoms (True)
- atoms cannot be made or destroyed (False)
- all atoms of same element are identical (False)
- different elements have different types of atoms (True)
- chemical reactions occur when atoms are rearranged (True)
- compounds are found from atoms of different elements (True)
-
He helped discover radioactivity.
-
Proved the exsistence of negatively charged particles, later called electrons.
-
He measured the charge of a single electron and mass.
-
An atom has a central postive nucleus surronded by negative orbiting electrons. Credited with nucleus and proton.
-
Depicted atom as small, postively charged nucleus surronded by electrons. Electrons travel in circular orbit.
-
Discovered isotopes of non-radioactive elements
-
atom consists of nucleus and clouds. Discovered formula that calculated the odds of where an electron might be. Proved Bohr Model incorrect
-
Discovered neutron.