Name________________________________________________________Date_________________Period___________
Chemistry I
Unit 6 Take Home Exam
DUE FRIDAY, JANUARY 20 AT 3:00 PM
Please follow directions.
Make sure you avoid procrastination. Excuses such as “my printer ran out of ink” or
“computer problems” are not tenable and may easily be avoided through timely effort
(good planning) and/or use of the resources here at school, including computers, printers,
web resources and reference material.
Late exams will be accepted but the raw score will be multiplied by 50%.
You are expected to be ethical in completing this exam. Some collaboration is expected
and is ethical. Collaborations that include giving or receiving answers, splitting up the
work, plagiarism of copyrighted material (including web pages) and the like are unethical.
Exercise your good judgment. Questions 3-10 must be submitted to www.turnitin.com.
Make sure you correctly attribute (give credit to in a bibliography) all work that is not
your own.
Exams must be typed or processed. Lewis structures and orbital diagrams may be
written longhand. Electron configurations should be typed or word processed.
Directions:
On the reverse of this page you will find a number of questions. Everyone must answer
the first three questions, for a total of 30 points. Also, everyone must submit a biography
of a scientist or team of scientists that contributed important work in the understanding of
atomic structure, for an additional 10 points (described further on the reverse of this
paper). For the biography question you must pick a name out of a beaker…this will help
me avoid having to read forty articles on Niels Bohr.
For the remaining 10 points, each student must choose a mix of questions that totals the
final 10 points. Only the first 50 points of questions will be scored - the mandatory 40
points and the other 10 points of student-chosen questions.
Do Work You Can Be Proud Of – Exceed Expectations!
The following are the three mandatory questions:
1. Write the complete electron configuration, orbital diagram, and Lewis dot diagram for the first
18 elements. The dot diagrams and orbital diagrams may be written longhand.
2. Write Lewis structures and predict the molecular geometries (using VSEPR theory) for the
following items. Show all valence electron pairs as lines and nonbonding valence electron pairs as
dots. For those structures that exhibit resonance, draw the various possible resonance forms.
Make sure you denote the proper charges on ions!
 Nitrate ion
 Nitrogen trifluoride
 Carbonate ion
 Sulfur dioxide
 Ammonium ion
 Sulfur trioxide
 Dichromate ion
 Hydrogen carbonate ion (the hydrogen
is bonded to the oxygen)
 Boron trifluoride
 HCN
3. Compare and contrast dipole-dipole attraction, Hydrogen bonding, and London dispersion
forces.
The mandatory biography question:
You will pick a name out of a container from the following list. Your submission must use at least
three references, with a maximum of two references from the web. You must include a
bibliography using a standard format (check your notes from English class). Your
submission must be at least one page with standard margins, 1.5 spacing and a readable 12-point
font. Import pictures and diagrams if possible (these are optional and are in addition to the one
page requirement). No “wiki” type sources may be used.
4. Demikritos/Leucippus, Rutherford, Crookes, Bohr, de Broglie/Heisenberg/Schrodinger, JJ
Thomson, William Thomson (Lord Kelvin), Dalton, Lewis, Seaborg, Meitner, Fermi.
Now choose from the following list until you have 10 more points-worth of questions. Make
sure your answers are complete. One- or two-sentence answers will probably be
insufficient for full credit.
5. Explain the relationship between wavelength and frequency, and then relate this to the energy
content of a photon. 5 pts
6. Explain the organization of the periodic table in terms of electron configuration. 5 pts
7. Explain the trends in ionization energies seen in groups of the representative metallic elements.
5 pts
8. Account for the fact that the line that separates the metals from the nonmetals is diagonal
downward to the right instead of horizontal or vertical. 5 pts
9. Explain why metals tend to lose electrons and nonmetals tend to gain electrons. Use the
periodic table to support your answer. 5 pts
10. Describe the types of bonds we discussed in class in terms of electron behavior. Also, explain
what is meant by the term ‘chemical bond’ then explain why a chemical bond forms. 10 pts.
11. Using only a periodic table, predict the most stable ion for Na, Mg, Al, S, Cl, K, Ca, Ga. Arrange
these elements from larges to smallest radius and explain why the radius varies as it does. Hint:
consider the particles that make up each ion, and the numbers present. 10 pts.
12. Compare and contrast the terms ‘orbit’ and ‘orbital.’ 5 pts