chemistry history of atom chpt 3

  1. Democritus
    atoms = indivisible
  2. Aristotle
    • matter is continuous and can be divided infinitely into smaller particles
    • was wrong
  3. Antoine Lavoisier
    law of conservation of mass
  4. Joseph Proust
    law of definite proportions (ratio is always going to be 2 H to 1 O)
  5. Dalton
    • atomic theory
    • 1. law of multiple proportions (CO, CO2) / law of definite proportions (formula)
    • 2. all elements are made up of indivisible atoms (WRONG)
    • 3. law of conservation of mass
    • 4. atoms of one element differ in properties from atoms of another element
    • 5. all atoms of a give element are the same (WRONG b/c of isotopes)
  6. Crooke
    • Crooke's tube (cathode ray tube)
    • rays deflected away from negatively charged magnet--> cathode rays are negatively charged particles
    • discovered electron
  7. Thomson
    • discovered proton
    • determined ratio of charge to mass
    • Plum Pudding Model
  8. Millikan
    • Oil Drop Experiment
    • measure charge of electron
  9. Rutherford
    • Gold Foil Experiment
    • bombarded gold foil with positively charged alpha particles
    • most went through foil, but few were deflected
    • atom mostly empty space
    • nucleus = dense core with positive charge
    • knew there was another particle in nucleus b/c mass was too large
  10. Chadwick
    discovered neutrons
  11. Marie Curie
    discovered radiation
  12. nuclear force
    optimum distance for attraction between forces in nucleus
  13. electrostatic attraction
    attraction between electron and proton
Author
kelly
ID
257029
Card Set
chemistry history of atom chpt 3
Description
chpt 3
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