The History of Atomic Theory

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The History of Atomic Theory
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Cartoon of the day
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Todays Warm-up

• Warm-up Black-box
• With your lab group of 4, investigate and predict
  (w/out opening) what is in your black box
• How did you come to that conclusion?
• What senses did you use?
• Did you use any tools?
• Can you think of any tools that would make your
  prediction more likely or accurate?

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Atomic Theory History Models
Notes
Questions Vocabulary words Formulas Main
Ideas Possible Test Questions Key Concepts
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Summary of the notes and information learned
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Todays Research

• Famous scientists who contributed to the atomic
  theory/atomic model (not in any order)
• John Dalton
• Aristotle and Democritus
• alchemists
• J.J. Thompson
• electron cloud model
• Niels Bohr
• Earnest Rutherford

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Atomic Structure Timeline

• Requirements (work in lab groups of 4)
• Must include a title.
• Must include a spot for each of the 7 items.
• Must include at least the Who, When, and What.
• Must have a picture/drawing (color is preferred)
  for each item.
• Options
• Comic book format
• Standard timeline
• PowerPoint slideshow
• Other???

History of Atomic Structure History of the
Atomic Model
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Ancient Philosophy

• Who Aristotle, Democritus
• When More than 2000 years ago
• Where Greece
• What Aristotle believed in 4 elements Earth,
  Air, Fire, and Water. Democritus believed that
  matter was made of small particles he named
  atoms.
• Why Aristotle and Democritus used observation
  and inference to explain the existence of
  everything.

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Democritus
Aristotle
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Alchemists

• Who European Scientists
• When 800 900 years ago
• Where Europe
• What Their work developed into what is now
  modern chemistry.
• Why Trying to change ordinary materials into
  gold.

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Alchemic Symbols
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Atomic Particle Theory

• Who John Dalton
• When 1808
• Where England
• What Described atoms as tiny particles that
  could not be divided. Thought each element was
  made of its own kind of atom. Developed the
  Atomic Theory
• Why Building on the ideas of Democritus in
  ancient Greece.

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Daltons Atomic Theory

• 1 Elements are composed of small indivisible
  particles (atoms)
• 2 Atoms of the same element are identical. Atoms
  of different elements are different.
• 3 Atoms of different elements combine together
  in simple proportions to create compounds.
• 4 In a chemical reaction, atoms are rearranged,
  but not changed.

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John Dalton
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Discovery of Electrons

• Who J. J. Thompson
• When 1897
• Where England
• What Thompson discovered that electrons were
  smaller particles of an atom and were negatively
  charged.
• Why Thompson knew atoms were neutrally charged,
  but couldnt find the positive particle.

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J. J. Thompson
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Atomic Structure I

• Who Ernest Rutherford
• When 1911
• Where England
• What Conducted an experiment to isolate the
  positive particles in an atom. Decided that the
  atoms were mostly empty space, but had a dense
  central core. (gold foil exp.)
• Why He knew that atoms had positive and negative
  particles, but could not decide how they were
  arranged.

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Ernest Rutherford
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Atomic Structure II

• Who Niels Bohr
• When 1913
• Where England
• What Proposed that electrons traveled in fixed
  paths around the nucleus. Scientists still use
  the Bohr model to show the number of electrons in
  each orbit around the nucleus.
• Why Bohr was trying to show why the negative
  electrons were not sucked into the nucleus of the
  atom.

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Niels Bohr
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Electron Cloud Model

• Electrons travel around the nucleus in random
  orbits.
• Scientists cannot predict where they will be at
  any given moment.
• Electrons travel so fast, they appear to form a
  cloud around the nucleus.

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Electron Cloud Model
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Atomic Structure Timeline

• Requirements
• Must include a title.
• Must include a spot for each of the 7 items.
• Must include at least the Who, When, and What.
• Must have a picture (color is preferred) for each
  item.
• Options
• Comic book format
• Standard timeline
• PowerPoint slideshow
• Other???

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Atomic Theory History Models
Notes
Questions Vocabulary words Formulas Main
Ideas Possible Test Questions
Notes
Notes
Notes
Notes
Notes
Notes
Notes
Notes
Notes
Summary of the notes and information learned
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Make it a great day Mustangs!