The Gold Foil Experiment was conducted under Ernest Rutherford’s supervision in 1909. In the gold foil experiment, a radioactive sample emits a beam of alpha particles. These particles go through a piece of gold foil. There was a fluorescent screen placed around the gold foil which glowed when contacted by alpha particles. This allowed the scientists to see where they contacted the screen as well as determine with that information whether the particles bounced off or went through the gold foil. The vast majority of the particles went through the foil which indicated that the majority of an atom's mass was concentrated in one small region. This simultaneously disproved the Plum Pudding model in which there was equal mass distribution throughout the entire atom. Lastly, the X's represent the particles and how they split as they hit the gold foil. A majority of the particles go straight, but minorities of the particles go in different directions as shown in the diagram. This placement meant that the atom's mass was mainly in the center of the atom as opposed to spread out. Press the green flag to see the experiment in action!
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