Drill

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Drill 10/12

• Who was your scientist from last class? Was his
  model of the atom what we accept today? Was it
  completely wrong?

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To Conclude

• What is our current model of the atom called?
• Are the previous models completely wrong?
• Next class is PSATs. Thursday we will review
  scientists and go into atomic conversions.

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Drill 10/13

• What is everything that is inside an atom?

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Thompsons Cathode Ray Tube Experiment
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Cathode Ray Tube Demonstration
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Cathode Ray Tubes

• Cathode rays are beams of current.
• They are emitted from a negative terminal, called
  a cathode, and travel to the positive terminal,
  called the anode.

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Magnets

• Magnets have a positive and a negative side.
• Positive is attracted to negative
• Negative is attracted to positive

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Cathode Rays

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Cathode Rays
Cathode Rays

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Cathode Rays
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Cathode Rays
Cathode Rays
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Cathode Ray Tube Demonstration
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Conclusions from the Cathode Ray Tube

• From these experiments, J.J. Thompson concluded
  that cathode rays are made up of negatively
  charged particles.
• It did not matter what element was put into the
  cathode ray tube, they all had negative particles
  that behaved the same way.
• These negative particles that all atoms have are
  called ELECTRONS!

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• Called the plum pudding model

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• Rutherfords Gold Foil Experiment

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(No Transcript)
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Rutherfords Experiment

• An experiment by Ernest Rutherford in 1911.
• He bombarded gold atoms with positively charged
  particles called alpha particles.
• Rutherford knew when the positively charged
  particles hit something because instead of
  passing straight through the gold foil they would
  bounce back or be deflected.

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Rutherfords Conclusions

• In Rutherfords experiment, it seemed that he was
  required to send an incredible number of missiles
  to get a hit.
• He concluded that the grid of the atom must be
  composed of tiny, tiny cells and only one cell
  contains all of the positive charge of the atom

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• The atom is made up of mostly empty space with a
  small positively charged nucleus in the center.
• We now know that protons and neutrons make up the
  nucleus.

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Bohr

• Planetary Model of the atom

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Heisenberg Schrödinger

• Their ideas together gave us the ELECTRON CLOUD
  model. This is our current atomic model.

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• Quarks make up protons and neutrons. 6 types
  of quarks differ in mass and charge up,
  down, strange, charmed, bottom, top.
• Leptons make up electrons
• Gluons hold quarks together (like glue!)
• Mesons composed of one quark and one antiquark.
  Responsible for the forces in the nucleus.

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Antimatter

• i. What do you think antimatter is?
• Where do you think antimatter came from?
• Where is all the antimatter now?