GREER
EXAM CHEM135 #1 SEPTEMBER 20, 2004
I pledge on my honor that I have not given or received any unauthorized assistance on this examination. NAME SECTION * Minus 5 points if section number is missing, name is not readable, or ID number is missing. * Fill in your name, etc, on every page before you start. * Be sure you have all 6 pages of the exam. * When you are asked for a numerical answer, give it with the proper number of significant figures. Show your work and draw a box around your final answer. * You have 50 minutes to complete the exam. ID#
SCORE: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. ___
TOTAL
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MISSING SECTION OR ID# ____ =
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NAME 1. (5 points) Questions about the syllabus, introductory lecture, and code of academic integrity: True or False: Write AT@ or AF@ after each statement: a) It is OK to eat your lunch during lecture in Chem 135.
b) The standard penalty for cheating is a grade of "XF."
c) You are a student in Chem 135/Greer. You need to have grades for 3 out of 5 exams. You take the first exam. You skip the second exam. You take the third exam. You skip the fourth exam. Then you are in a car accident and have surgery that keeps you in the hospital until two days before the fifth exam. You don't have to worry because Dr. Greer will make an exception in your case.
d) If you find a mistake in grading your exam, Dr. Greer will be happy to regrade the exam for you, but she will regrade the entire exam and you could possibly lose points.
2. (7 points) (a) Give the (correctly-spelled!) name of the element for which each of the following is the symbol: He Be F (watch out for this one!)
(b) Give the symbol for each of the following elements: Lithium Nitrogen Neon 2
NAME
3. (12 points) Express the result of each calculation in exponential with notation, the proper number of significant figures. The math is easy and can be done in your head! 145.8 + (2.3 X 10-1)
8,400 X 10-3
/ 2.0 X 104
(2.54 cm/in) X 2.000 in
4. (10 points) Silicon is very important to materials and electrical engineers! When an irregularly shaped chunk of silicon weighing 8.763 g was placed in a graduated cylinder containing 25.00 mL of water, the water level in the cylinder rose to 26.76 mL. Show how you would calculate the density of silicon in g/cm3. You do not need to do the math - just set it up, but be sure you show how the units work out.
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NAME
5. (20 points) Do the following unit conversions. Use exponential notation where appropriate, keep the proper significant figures, and use the correct abbreviations. Show enough work that we can tell that you know what you are doing. Do the math.
What is 14 ps in attoseconds?
What is 10 cm3 in liters?
What is one D in femtometers?
Tungsten melts at 6192 EF. Show how you would convert this toEC and to K. Show proper units. Do a final approximate calculation by letting 5/9 be about 1/2.
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NAME 6. (9 points) Indicate the number of protons, neutrons, and electrons for each of the following: protons
15
neutrons
electrons
7
N
27
60
Co
1
3
T
7. (3 points) Identify the following elements by symbol:
12 24
X
28
58
X
46
104
X
8. (21 points) Give the allowed quantum numbers for each of the following electrons:
3s
2p
5
3d
6
NAME
9. (6 points) Give the orbital designations for the following quantum numbers:
n = 1, l = 0
n = 3, l = 1
n = 4, l = 3
10. (7 points) Write the reactants and products for the two demonstration we did in class - you do not have to balance the equation (this time!) Explosion of hydrogen balloon
Addition of sodium to water
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