28Thomson’s DiscoveryHe determined that the cathode ray was made of negatively charged particles – electrons.
29Cathode RaysThomson also was able to estimate that the mass of the electron was equal to about 1/1840 of the mass of a hydrogen atom.His discovery of the electron won the Nobel Prize in 1906.
30Cathode RaysThompson showed that the production of the cathode ray was not dependent on the type of gas in the tube, or the type of metal used for the electrodes.He concluded that these particles were part of every atom.
31Charge of the Electron Charge of Electron 1.6 x 10-19 C (coulombs) Mass of Electron9.11 x g
47Rutherford's Experiment Most particles passed through with no deflection, while some were highly deflectedRutherford concluded that most particles passed through because the atom is mostly empty space.
48Rutherford’s Conclusions All of the positive charge, and most of the mass of an atom are concentrated in a small core, called the nucleus.
49Size of Nucleus Compared to the Atom is as a Ball Compares to a Football Field.