-
Matter is made of small indivisable particles which have different form , position and arrangment Democritus named these Atoms.
-
Developed an atomic theory stating that spherical atoms had measurable properties of mass.
-
Used Cathode ray tubes to discover that " canal rays " have opposite properties of electrons.
-
Discovers the electron and used cathode ray tubes to determine the charge to mass ratio of an electron to be 1.759 x 10^8 coulombus/grams.
-
Performed an oil drop experiment to determine the charge and mass of an electron to be 1.603x10^-19 C and 9.11x10^-28g respectivly.
-
Finds that an atom has a small dense positively charged nucleus , electrons move around the nucleus.
-
The electron moves in a circular orbit at fixed distances from the nucleus.
-
Developos mathematical equations to describe the motion of electrons in atoms. His work leads to the electron cloud model.
-
Confirms the existance of neutrons which have no charge.Atomic nuclei contain neutrons and positivly charged protons
