Atoms and The Periodic Table

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Atoms andThe Periodic Table
KD McMahon Reseda Science Magnet
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Aristotleand Democritus
Aristotle
Essence/Form
Potential --gt Actual
Four Elements
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Aristotleand Democritus
Democritus
a tome not cut
makes up everything
many different kinds
exist forever
only matter
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John Dalton
Atoms of same element are identical
atoms combine --gt whole ratios --gt
compounds
chem Rxs atoms separate recombine
no transmutation
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Review Questions

• Why did Democritus call his fundamental particle
  of
• matter the atom?

2. Why was Democritus theory rejected for so
many centuries?
3. Based on Daltons atomic theory what would be
wrong with the following formula for water
HO1/2
4. According to Dalton would it have been
possible for alchemists to have turned lead
into gold?
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JJ Thomson
Used cathode ray tubes
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JJ Thomson
Used cathode with paddle wheel
What did he conclude?
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JJ Thomson
Used cathode with oppositely charged plates
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JJ Thomson
Used cathode with oppositely charged plates
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JJ Thomson
Used cathode with oppositely charged plates
What did he conclude?
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JJ Thomson
From these results he came up with
The Plum Pudding Model of the Atom