Democritus -Greek philosopher 450 BC
Aristotle
-born 384 BC
-Greek philosopher,educator & scientist
-student of plato
Lavoisier-French chemist 1700’s -“Law of Conservation of Mass”
2 Mg + O2 2 MgO 10.0g 6.58g 16.58g
16.58g 16.58g
Joseph Proust-1754-1826
-French Chemist
-Law of Definite Proportions
H20Looking at …
JohnDalton
-English school teacher & scientist
-Early 1800’s
-Atomic Theory of Matter
-Law of Multiple Proportions
Dalton’s Periodic Chart
Dalton’s Model of an Atom
William Crookes
-1832-1919
-English Chemist
-developed the cathode ray tube
Cathode Ray Tube in Action
Cathode Ray Tubes
Michael Faraday-1791-1867
-English chemist and Physicist
-Electromagnetic induction
Induction
Ben Franklin
-1706-1790
-scientist, inventor, statesman
-looked at electrical charges
Chadwick-studied alpha particles to discover neutrons
-English physicist early 1900’s
-Worked with cathode ray tubes
JJ Thomson
Electron Beam in CRT
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Plum Pudding Model
Ernest Rutherford-New Zealand Scientist early 1900’s -Alpha scattering experiment
98% of the particles passes straight through 2% of the particles deflected off at varying angles 0.01% of the particles bounced straight back
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Rutherford’s Model of an atom
Max Planck-German Physicist
-1858-1947
-studied light emitted from objects
E = h v
Planck’s Theory … What does it mean?
Photoelectric Effect
Albert Einstein
-1879-1955
Niels Bohr
-Danish physicist early 1900’s
-Used Rutherford’s planetary idea
-Used Plank’s idea of “quanta”
Planetary model of an atom
Robert Millikan-1868-1953
-American physicist
Milikan’s Oil Drop Experiment
On-line Model
Werner Heisenberg
-1901-1976
-Uncertainty Principle
Erwin Schrodinger
What’s that? Sign your planner?We’re talking quantum mechanics here folks …
Schrodinger wave model of an atom
orbitron
Henri Becquerel
Marie and Pierre Curie
Henry Moseley
-1887-1915
-Rutherford’s student