Transcript Do Now 2 theory

“DO NOW” #2 –page 312
 II. A MODEL ATOM
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A. Development of the Atomic
Theory
1. Who was Democritus and
what was his contribution to
science?
2. Who was John Dalton?
Draw his model.
3. What did J.J. Thomson
discover in the atom? Draw his
model.
4. The dense positively
charged center of an atom is
called the ___________.
5. Rutherford discovered a
positive charged particle in the
atom called the ___________.
 6. What did Neil Bohr
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discover? Draw his model.
7. What did James
Chadwick discover? Draw
his model.
8. Explain why each
energy level is different.
9. How many electrons
does each level hold?
10. Find the symbol,
atomic #, and mass # of
these elements: Hydrogen,
Helium, Titanium,
Aluminum, Argon,
Chromium.