-
John Dalton's Atomic Theory
1.) All matter is made of indivisible atoms (atoms that can be continually broken down into smaller pieces.) 2.) All atoms of the same element are identical to one another. 3.) Atoms can be neither created or destroyed 4.) Atoms can have different weights and chemical properties if they are not of the same element. 5.) Atoms of different elements can be combined, making simple numbers into larger compounds. -
JJ Thompson
1.) Proved that cathode rays were particles. 2.) Found that cathode rays could be deflected by electric fields. 3.) Found that the particle mass ratio was 10^8 Coulomb (C) per gram. 4.) Found that atoms are heaver than electrons and matter is electriclly neutral. Note: His conclusion was that, "Particles were a universal component of matter (Thompson)." -
Ernest Rutherford's Gold Foil Experiment
(Note: The month and the day is not correct; could not be found) Note: was finalized in 1911 Experiment:
1.) Rutherford studied how alpha particles were deflected through thin gold foil sheets. 2.) He found that most of the particles could penetrate stright through the gold foil sheets, although some were deflected at slight angles, and others were deflected at angles over 90 degrees. 3.) The particles that deflected at angles over 90 degrees only happened in about 1 out of ever 20,000. -
Niels Bohr's Planetary Model
(Note: The month and the day is not correct; could not be found; only the year is correct!) Devekoped a model of the atomic structure. His model showed the build up of atoms made of electons and orbital shells. His conclusion was that electrons can move from one energy to another, by either gaining or losing that energy.
