The Model Of The Atom Before Thomson And Rutherford

2.5 – Nuclear Physics
What was initially known about the model of the atom before Thomson and Rutherford conducted their experiments?
The first model of the atom is thought to have come from two Greek philosophers - Democritus and Leucippus – in the fifth century BC. These two philosophers believed that everything was made up of matter, and that you could half a given portion of matter (and keep halving the product) and eventually be left with something that couldn’t be halved again: the atom. They believed that all atoms were imperishable and could not be split apart. The very word we use today (atom) comes from this key idea, with the Greek word ατoμoν (atom) meaning indivisible, linking with the concept that matter (atoms, as they were now
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These contents of these tubes are in a vacuum (no air inside), where the tube contains two oppositely charged electrodes - one on each side. One of the electrodes (the cathode) fires electrons at the other (the anode) when voltage is added to the system. When Thomson turned the tube on, he saw a beam of "light" between the two electrodes. To figure out what this “light” was, he applied a magnetic field to the contents of the tube and found out that the beam moved toward a positive charge and away from a negative charge. From this, Thomson determined that these little cathode rays (which we now call electrons) had negative charge. Thus, Thomson realized that the currently accepted model of an atom did not account for negatively or positively charged particles, leading to his suggestion of the Plum Pudding model. Thomson 's model of the atom did explain some of the electrical properties of the atom due to the electrons, but failed to recognize the positive charges in the atom as particles, where they are known today as protons in the …show more content…
Rutherford determined this by his gold foil experiment, where he fired alpha particles through a vacuum (so as that they do not dissipate) at a very thin layer of gold foil, observing that the majority of alpha particles went straight through, however, some were deflected by a relatively short amount (due to the positive charge of the nucleus interacting with the positive charge of the alpha particle and thus repelling) and some were reflected backwards, or deflected by an extreme angle. This suggested that the alpha particle hit a very dense particle and bounced off. From here, Rutherford ascertained that the atom had a planetary model, with a positively charged nucleus that was very tiny and dense, and a cloud of electrons that presumably orbited the nucleus.
Were there any issues with Rutherford’s model of the

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