Ernest+Rutherford

Ernest Rutherford [] [] Describe the set-up for Rutherford�s Gold Foil Experiment. Include a visual. What was he doing in the experiment? Explain the outcome of the Gold Foil Experiment. Summarize his model of the atom. Rutherford�s model changed our view of the atom. Compare and contrast his model to Thomson�s model. What new knowledge did we gain? What was wrong with Thomson�s model? Did any of Thomson�s ideas continue to be valid?

1) Describe the set-up for Rutherford�s Gold Foil Experiment. Include a visual. What was he doing in the experiment? The alpha particles were generated by a decay of radium and then was directed to a sheet of thin gold foil, surrounded the gold foil was a sheet of zinc this was used as a detector. When hit with the alpha particles the zinc sheet would light up. 2) Rutherford saw that most of the alpha particles went straight through exsisting holes in the gold foil, he also observed that some of the particles deflected through angles larger than 90 degrees if they did not go through the holes 'Pre-made' in the Gold Foil. . 3) Rutherford suggested that the atom had a dense, small core (the nucleus) which had positively charged particles in the middle surrounded by a ring of electrons. Because the atoms were too dense, they would bounce off the gold plate instead of bursting into millions of pieces, if they hadn't gone through any exsisting holes in the plate. The alpha particles would pass right through the atom. Rutherford�s atom looked like a tiny solar system with the nucleus always in the center and electrons moving around it.



4) Thomson suggested that the atom was a jigsaw puzzle made of small pieces. He discovered that the glowing stream would bend toward a plate that was positively charged. Thomson thought that the glowing stream was made up of particles that had a negative charge. These negative particles were later called electrons. Then later Thomson thought the atoms looked like raisin bread, later Rutherford proved him wrong.