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Observational Atomic Structure [KEY]
Analytical Chemistry
Department of Science, Honors Chemistry | Spring Chapter 4 Section 2 Review

Essential Questions & Answers:
[ ] 1. Who suggested the ideology of atoms?
4th century B.C Greek Democritus of Abdera
[ ] 2. What was the conclusion, in reference to the concept of atoms, Democritus proposed?
Atoms were indivisible, indestructible, fundamental units of matter.
[ ] 3. What did Democritus’ proposals lack in explanatory reasoning? Why?
They lacked experimental support.

[ ] 4. Who essentially continued the work of Democritus with the use of experimental proof? John Dalton. Based on his experimental work he was able to conclude the following hypothesis (also known as Dalton’s Atomic Theory): “1. All elements are composed of submicroscopic indivisible particles (atoms!) 2. Atoms of the same element are identical. 3.
Atoms of different elements can physically mix or chemically combine. 4. Chemical reactions occur when atoms are separated, joined, or rearranged. ”
[ ] 5. An atoms concerned unit (that is smaller) is also known as?
A quark.
[ ] 6. A quarks concerned unit (that is smaller) is also known as?
Cosmological String; Superstring Theory, vibrates in a restricted domain because of theoretical dimensions (one reason for the request of the LHC(Large Hadron Collider); to prove theoretical dimensions, ejected gravitons would have proved this) or LQG.
[ ] 7. Who concluded the existence of electrons? How?
English Physicist Sir J. J. Thomson discovered in 1897. Sealed gases in glass tubes with electrodes positioned at each end connected to a high voltage source of electricity. This resulted in a cathode ray.
LABORATORY PRACTICAL #1: Using the same methodology that Thomson used, please set up the cathode tube (materials provided) to get the same output (observation) Thomson did.
Hydrogen(H2(g)) will be provided. Please write a Laboratory Practical Report. Due date is scheduled on the course calendar (please consistently check the due dates as they are subject to change). More information on this lab is listed in the lecture titled “Chapter 4.2.1
Laboratory Repertoire A.pdf” Call your instructor over for a grade.
(100 PTS) rubric on website. (401 PTS) Students are given 45 minutes to reproduce the experiment (each)

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[ ] 8. Who concluded the existence of protons? How?
E. Goldstein in 1886. Used a cathode ray tube (cathodes contained holes). Rays traveling in opposite directions to the cathode ray.
LABORATORY PRACTICAL #2: Using the same methodology that Goldstein used, please set up the cathode tube (materials provided) to get the same output (observation) Goldstein did.
Please write a Laboratory Practical Report. Due date is scheduled on the course calendar
(please consistently check the due dates as they are subject to change). More information on this lab is listed in the lecture titled “Chapter 4.2.2 Laboratory Repertoire B.pdf” Call your instructor over for a grade. (276 PTS) rubric on course website. Students are given 45 minutes to reproduce the experiment (each).

[ ] 9. Who concluded the existence of neutrons?
English Physicist Sir James Chadwick