-
Benjamin Franklin
Discovered that lightning was made of electricity -
John Dalton
Presented the ideas that became the foundation for atomic theory. Thise being:
All matter consists of indivisabe atoms.
Atoms of a perticular element are identical in weight and have identical properties.
Atoms if each element have a unique weight.
Atoms are neither created or destroyed in reactions.
Compounds are formed from the combination of atoms of 2 or more elements
The proportion and kind of atom is fixed in a given compound
Atoms combine in simple numerical ratios -
William Crookes
Invented the Crookes tube, which was later used in the discovery of electrons. -
Wilhelm Roentgen
Discovered X-rays, A type of radiation that originated from the atom and carried no charge. -
Henri Becquerel, Marie and Pierre Curie
Discovered radioactivity
Deduced that pitchblend was radioactive -
J. J. Thomson
Discovered that the atom could be split.
Discoered the electron.
Worked with the Cathode ray tube to discover that electrons were negativly charged.
Created the Plum Pudding model. -
Ernest Rutherfrd
Disproved Plup pudding model
Discovered the proton
Discovered that atoms had a nucleus where most of the the mass was concentrated
Created the planitary model in 1911 -
Neils Bohr
Suggested that electrons were aranged in 'shells' around the nucleus . He suggested that electrons could become excited by electricity, heat and light, causing them to 'jump' to the next electron shell, and when they return they will emit a small quantum of energy -
James Chadwick
Discovered the neutron by obserfing a particle in a cloud chamber which was not deflected by a magnetic field.