Name__________________________________________
Sample Exam Questions #2 (Chapters 5, 8, 16, 9)
Chemistry 112
Multiple Choice
1. The hump of the camel contains stores of
a) water
b) carbohydrates
c) proteins
d) triglycerides
Reaction Pathway
A
Reaction Pathway
B
Energy
Energy
Energy
Energy
2. Which of the following represents the fastest, thermodynamically favorable reaction?
Reaction Pathway
Reaction Pathway
C
D
3. Which of the following would dissolve in your coffee the fastest? (Assume equivalent
masses.)
a) powdered sugar
b) table sugar
c) sugar cubes
d) a lollipop
4. A biological molecule is found to contain carbon, hydrogen, oxygen, nitrogen, and
phosphorus. It is most likely to be a
a) carbohydrate
b) nucleic acid
c) protein
d) lipid
5. The small organic molecule succinate is an intermediate in sugar metabolism. The enzyme
that catalyzes conversion of succinate also binds malonate, which is structurally similar to
succinate. If malonate does not undergo reaction, what is its role in this reaction?
a) substrate
b) inhibitor
c) product
d) catalyst
6. Medically speaking, why is consumption of human brains potentially hazardous?
a) Nonpolar drugs accumulate in brains, potentially leading to overdoses.
b) Brains can be infected with prions, leading to the human form of mad cow disease.
c) Brains are high in saturated fat and cholesterol, leading to increased risk of heart attack.
d) Radioactive iodine accumulates in the thymus of the brain.
7. The function of an enzyme depends on which of the following?
a) the sequence of its amino acids
b) its three-dimensional structure
c) specific interactions with its substrate
d) all of the above
8. Chromatography is:
a) used to separate molecules in a mixture based on properties such as polarity
b) used to separate biological molecules with an electric field
c) used to identify molecules based on interactions with electromagnetic radiation
d) a general name for several types of tests that use color change to detect cocaine
9. A bag seized during a drug bust is believed to contain cocaine. Which of the following would
be most conclusive that the material is cocaine?
a) The material is a white powder.
b) The material gives a positive result in the Scott test.
c) The bag is labeled “cocaine.”
d) The mass spectrum of the material is identical to that of a cocaine standard.
10. Who founded the world’s first crime laboratory?
a) Sherlock Holmes
b) Edmond Locard
c) Gil Grissom
d) Henry Faulds
11. Which of the following is the major advantage of PCR-STR when compared to RFLP?
a) PCR-STR uses nuclear DNA, which is more unique.
b) PCR-STR can be used on any biological sample, whereas RFLP analysis can be done
only on blood.
c) PCR-STR detects differences in genes, whereas RFLP monitors non-coding DNA.
d) PCR-STR can be done on much smaller amounts of material.
12. Which of the following is not a macronutrient?
a) water
b) carbohydrates
c) lipids
d) proteins
13. How does the body regulate blood sugar levels?
a) The rate of digestion slows or speeds up depending on blood sugar levels.
b) Insulin signals cells to take up glucose when blood sugar is high.
c) Insulin signals the liver to release glucose when blood sugar is low.
d) The brain uses less sugar when blood sugar is low.
14. Low-density lipoproteins are the blood carriers of
a) lactose
b) oxygen
c) fatty acids
d) cholesterol
15. Which of the following is the function of the B vitamins in the human body?
a) To provide extra energy to the cells
b) To assist enzymes during metabolism
c) To be used as building blocks for the production of new proteins
d) To eliminate unnecessary waste products from the body
Short Answer
1. Circle all examples of potential energy below. (Flash is my dog.)
Flash taking a nap
Flash at the top of a hill on a sled
Flash’s body fat
Flash’s dinner
Flash ready to jump off a dock
Flash chasing a soccer ball
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2. a) Draw the energy diagram for the energetically favorable reaction of diamonds converting
to graphite, labeling the reactant and the product.
b) On the same diagram, draw the same reaction in the presence of a catalyst.
c) Why doesn’t all your diamond jewelry convert to graphite, given that this is the
energetically downhill direction for this reaction?
3. Next to each statement below, write the corresponding law of thermodynamics.
_____
You can put a pig into a machine and get sausage, but you can't put sausage into the
machine and get the pig back.
_____
You can’t get there from here.
_____
My shoe is off; my foot is cold, I have a bird I like to hold.
_____
You can’t make an omelette without breaking a few eggs.
4. Circle all the exothermic processes below. Put an “X” in the box next to any processes for
which entropy increases.
fireworks going off
photosynthesis: 6 CO2 (g) + 6 H2O (g)  6 O2 (g) + C6H12O6 (s)
cold pack reaction: NH4NO3 (s)  NH4+(aq) + NO3- (aq)
sublimation of H2O
burning wood
5. You are going on a backpacking trip and have to carry all your own food.
a) Which would provide the most energy: a pound of fat, a pound of sugar, or a pound of
protein? (Circle one choice.)
pound of fat
pound of sugar
pound of protein
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all are equivalent
b) In terms of good health, does it matter what source of energy you bring? (That is, would
fats, sugars, and proteins all be equivalent?) Briefly explain.
6. For each type of evidence below, name the best technique for its analysis at the crime lab
and give a one-sentence description of the data produced and its interpretation.
a) tissue sample from Anna Anderson to determine whether she was Anastasia Romanov
b) debris collected from a possible arson
c) bag of white powder seized in a drug bust
d) blonde hair recovered from the rape of a brunette
7. Fill in the letter(s) of the appropriate description(s) for each of these molecules. A molecule
may have more than one description.
Molecules:
__________ Carbohydrate
__________ Lipid
__________Protein
__________Nucleic Acid
Descriptions (may be used more than once):
A) building block of cell membranes
B) composed of amino acid building blocks
C) composed of monosaccharide building blocks
D) generally contains only carbon, hydrogen, and oxygen
E) most useful in forensic settings
F) the molecule shown here belongs to this class of compound
H2
C
H3C
CH3
H2
C
H2
C
H2C
CH
HO
4
H2C
CH3
CH
C
C
C
H2
C
CH
CH
C
H2
C
H2
CH3
CH
CH3
CH2
CH2
C
H
CH
H2
C
8. Sickle cell anemia is an example of a genetic disease.
a) What protein is affected in sickle cell anemia and how does this cause disease?
b) Mad cow disease is also caused by a problem with a protein. How does this disease differ
from a genetic disease?
Problems. You must clearly show your work for full credit.
1. This question is
about the energy bar
with the label shown
here.
a) How many
Calories are in
this energy bar?
b) With the correct number of significant figures, how many joules is this? If you didn’t get
an answer for part a, use 100 Calories and do this question anyway. (Hint: 1 cal = 4.184
J)
2. A closed vessel contains 104 g of C2H2 and 300 g of O2 that react to form carbon dioxide
and water. 236 kJ of heat are released per mole of C2H2.
a) Write the balanced equation for this reaction.
b) How much heat is released in this reaction?
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