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Exam 4 Review
Supplemental Instruction
Iowa State University
Allison
Chem 163
Dr. Appy
11/16/14
1. Determine the oxidation state of each element in the following compounds:
a. Cr2O7 2-
b. NO2
c. CaH2
d. SO4 2-
e. MnO2
2. Define reduction and oxidation.
3. Identify the species being oxidized and reduced in each of the following
reactions:
a. 2 Cr+ + Sn4+ ----> Cr3+ + Sn2+
b. 3 Hg2+ + 2 Fe ----> 3 Hg2 + Fe 3+
c. 2 As + 3 Cl2 ----> 2 AsCl3
d. 2 NaBr + Cl2 ----> NaCl + Br2
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4. Construct a battery with the following equation. Label the anode, cathode,
the flow of electrons, and a salt bridge.
5. Using the EMF series, decide which of the following redox reactions is
spontaneous.
a. 3 Ag+ + Au3+ ----> Au + 3 Ag+
b. Au + 3 Ag+----> Ag+ + Au3+
6. Describe the following relationships:
a. Pressure-Volume Relationship
b. Pressure-Temperature Relationship:
c. Pressure-Moles (n) Relationship:
7. Knowing these relationships, what happens when…
a. You double the absolute temperature of the gas?
b. You double the number of liters the container can hold?
c. You double the number of moles (n) of the gas?
8. If I have 4.0 moles of a gas at a pressure of 5.6 atm and a volume of 12 liters,
what is the temperature?
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9. If I have an unknown quantity of a gas at a pressure of 1.2 atm, a volume of
31 liters, and a temperature of 87 0C, how many moles of gas do I have?
10. If I contain 3.0 moles of gas in a container with a volume of 60. liters and at a
temperature of 400. K, what is the pressure inside the container?
11. If I initially have a gas with a pressure of 8.4 atm and a temperature of 35 0C
and I heat it an additional 230 degrees, what will the new pressure be?
Assume the volume in the container is constant.
12. A 24.5-gram sample of an unknown gas occupies a volume of 44.5 L at 273.0
0C and 0.100 atm. What is the molar mass of the sample?
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13. What is the molar mass of an unknown gas if 12.04 grams of the gas occupies
7.40 L at 27.0 0C and 980 mm Hg? (1 atm=760 mm Hg)
14. What happens to the pressure inside a steel container if the temperature of
the container is decreased from 25.30C to 5.20C, and the number of moles of
gas inside the container is increased from 2.32 moles to 8.63 moles? The
volume of the container is 40.0 L and the initial pressure within the container
is 170.0 atm.
15. Define:
a. Solution:
b. Solvent:
c. Solute:
16. How many mL of a 1.500 M solution of NaCl do you need to obtain100.0 g of
NaCl?
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17. A solution is prepared by mixing 100.0 g of glucose (C6H12O6) with enough
water to make 500.0 mL of solution. Calculate the molarity of the solution.
18. How many milliliters of the solution in Question 17 are needed to provide
35.0 grams of glucose?
19. Describe how you would prepare 250.0 mL of a 0300 M solution of KCl from
solid KCl and water.
20. Calculate the percent by mass of a solution that is prepared by mixing 35.0
grams of ethanol (C2H5OH) and 150.0 grams of water.
21. Calculate the percent by volume of a solution that contains 25.0 mL of
ethanol in 100.0 mL of a solution.
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Useful Equations and Constants:
1 mole = 6.022 x 1023 things
PV = nRT
PiVi/(niTi) = PfVf/(nfTf)
MM = mRT/(PV)
MiVi = MfVf
R = 0.0821 L*atm/(mol*K)
STP = 0 °C and 1 atm
K = °C + 273.15
ΔTf,b = Kf,b x moles of solute / (Kg solvent)
P = F/A
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