sRead through the web sites and answer the questions about the development of the atomic model.
image from http://en.wikipedia.org/wiki/Democritus
Go to http://en.wikipedia.org/wiki/Democritus
1) What did Democritus believe about matter?
2) What word do we get from his description?
3) When did he do this?
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image from http://www.scienceclarified.com/everyday/Real-Life-Chemistry-Vol-1/Atoms.html
Go to http://northspringer.tripod.com/HistoryofAtom/id1.html
1) When did John Dalton originate the idea of an atomic theory?
2) In his book, Chemical Philosophy, how did he propose to identify elements?
3) What were John Dalton’s basic ideas about matter?
Go to http://antoine.frostburg.edu/chem/senese/101/atoms/dalton-quiz.shtml
Based on your understanding of Dalton ’s ideas, answer the questions on the quiz.
How many questions did you answer correctly?
Go to http://www.chemsoc.org/timeline/pages/1803.html
Sketch a drawing of Dalton ’s idea of an atom.
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image from http://www.chemheritage.org/classroom/chemach/images/smfotos/05atomic/thomson1.jpg
Go to http://www.aip.org/history/electron/jjhome.htm
1) What British physicist was studying the inside of the atom?
2) How long ago did he do this?
3) Through his experiments with electricity and cathode rays,
what did he discover about these rays?
4) How did this discovery disprove Dalton ’s idea of the atom?
5) What are cathode rays made up of?
image from http://online.cctt.org/physicslab/content/Phy2HON/lessonnotes/modern/bentbeam.jpg
**Why do you think the cathode ray is bending downward?
image from http://www.cartage.org.lb/en/themes/sciences/Physics/Atomicphysics/Atomicstructure/CurrentModel/millikan.gif
go to
http://www.uwcsea.edu.sg/phy/Millikan%20Experiment%20outline.htm
1) Who performed the oil drop experiment?
2) When?
3) What did he discover?
Put on head phones (or turn on speakers) and go to: http://chemistry.umeche.maine.edu/~amar/fall2004/Millikan.html
4) How did this experiment further disprove Dalton ’s ideas?
Go to
http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/P24_E/Thomson_model_E.htm
Sketch a picture of the atom at this time.
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image from http://www.neoam.cc.ok.us/~rjones/Pages/online1014/chemistry/chapter_8/images/scatter1.gif
Go to http://www.bcpl.net/~kdrews/introterms/intro7.html
1) How did Ernest Rutherford perform his experiment?
2) When the alpha particle bounced off the gold nucleus, what conclusion can be made about the atom?
3) How dos this discovery disprove Dalton ’s idea about the atom?
Sketch a picture of Rutherford ’s Planetary Model of the atom.
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image from http://daugerresearch.com/orbitals/index.shtml
Go to http://csep10.phys.utk.edu/astr162/lect/light/bohr.html
1) When did Niels Bohr propose his theory about the atom?
Sketch a drawing of the Bohr atomic model of the atom.
The correct theory of the atom is called q___ m___ (which you will study later).
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image from http://www.chemcases.com/nuclear/nc-01.htm
Go to http://www.chemcases.com/nuclear/nc-01.htm
1) What did Sir James Chadwick discover about the atom?
2) In what year did he make this discovery?
3) Before this time, what particles did the atom contain?
4) How did Chadwick discover the neutron?
5) How does the neutron affect an atom of an element?
Go to http://www.broadeducation.com/htmlDemos/AbsorbChem/HistoryAtom/page.htm
Answer this quiz. How many questions did you answer correctly? ______
Of all the experiments that you researched, which experiment had the greatest impact on science?
In your opinion, which experimental set up was the most creative?
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