John Dalton (Atomic Theory)Matter is made up of indivisible atoms.
All atoms of an element are identical.
Atoms are neither created nor destroyed.
Atoms of different elements have different weights and chemical properties.
Atoms of different elements combine in simple whole numbers to form compounds.
J.J. ThompsonFound that cathode rays could be deflected by an electric field.
Ernst RuthfordStudied absorption of radioactivity.
Rutherford updated Thomson's Raisin Pudding Model of the atom.Studied the deflection of alpha particles as they were targeted
at thin gold foil sheets.
H.G.J. MoseleyStudied the frequencies of the x-rays given off by cathode- ray tubes when electrons strike by anode.
James ChadwickProved that neatrons partiles in the nucleus that made up approximately half the mass of an atom, did exist.