Describe Thomson’s “plum pudding” model of the atom, and then explain how the results of Rutherford’s gold foil experiment resulted in a change to the atomic model.

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anonymous · Answer

At the time of Rutherford's gold foil experiment, the atom was assumed to have the structure of a sphere, with the neutrons floating around in a sea of electrons. The name "plum pudding" refers to this: the plums representing the neutrons, spread throughout. 

What happened with the gold foil experiment is, when electrons were fired through a sheet of gold foil, they bounced off in many directions. The only way this could happen is if they were bouncing off of something large in the atoms of the gold foil. They hypothesized that instead of neutrons floating around in the atom, they were gathered together in the center of the atom, creating a dense nucleus that the electrons were bouncing off of. Thus, the new atomic model. Does that make sense?