CH 233H
Second Midterm Exam
Friday, May 15, 2015
Name____________________________________________________________
Please show your work for partial credit.
You may not use notes or other materials with chemical information without the
instructor’s approval; necessary information is provided on pages at the back of the
exam. Please do not use ipods or other music players.
1. (15 points) Name the following linear alkanes.
2. (10 points) Circle and name the functional groups in each of the following molecules.
3. (15 points) Identify each of the following pairs of molecules as identical, constitutional
isomers, stereoisomers, or different (unrelated) compounds.
4. (30 points) The energy levels and two different pictorial representations of the π molecular
orbitals of ozone (O3)are shown (constituent AOs, left; actual calculated MOs, right). There are
4 electrons that occupy these MOs.
-4.855 eV
-10.407 eV
-17.257 eV
A. Illustrate on the diagram above where the electrons go. Label each MO as bonding,
antibonding, or nonbonding.
B. Draw the major resonance forms of ozone. Be sure to use proper Lewis structures,
including formal charges.
C. Explain how the MO bonding picture is consistent with the assignment of formal charge
you used in the resonance structures.
5. (30 points) Shown below on the left is an example of one of the glyceride molecules that
are the major constituent of fat. On the right is the structure of permethrin, a fat-soluble
insecticide molecule.
A. Explain why organisms would tend to accumulate permethrin in fat tissue.
B. Two metabolic reactions for permethrin occur in the human liver. The enzyme cytochrome
P450 performs an oxidation reaction, and an esterase enzyme hydrolyzes the ester to form a
carboxylic acid and an alcohol. Explain how either of these reactions helps the body process
and excrete this molecule.
Selected data that may be of use:
Physical constants:
g = 9.8 m/s2
ε0 = 8.85419 × 10-12 C2/(Nm2)
c = 2.99792458 × 1010 cm/s
R = 0.08206 L-atm/(mol-K) = 8.314 J/(mol-K)
N = 6.022 × 1023
k = 1.381 × 10-23 m2kg/(K-s2)
h = 6.626 × 10-34 m2kg/s
F = 96485 C/mol
π= 3.14159
e = 2.71828
Gravitational Constant
Electric susceptibility of a vacuum
Speed of light
Gas constant
Avogadro’s Number
Boltzmann constant
Planck’s constant
Faraday’s constant
Properties of State
Species
CH4 (g)
H°f
-74.6 kJ/mol
S°
188.7 J/(mol-K)
O2 (g)
0 kJ/mol
205.1 J/(mol-K)
CH3OH (l)
-238.4 kJ/mol
127.2 J/(mol-K)
CH3OH (g)
-205 kJ/mol
239.9 J/(mol-K)
H2O (l)
-285.8 kJ/mol
69.91 J/(mol-K)
H2O (g)
-241.8 kJ/mol
188.8 J/(mol-K)
CO2 (g)
-393.5 kJ/mol
213.7 J/mol-K
Ag (s)
0 kJ/mol
42.55 J/(mol-K)
Ag+ (aq)
105.6 kJ/mol
72.68 J/(mol-K)
K+(aq)
-254.4 kJ/mol
102.5 J/(mol-K)
Zn (s)
0 kJ/mol
41.63 J/(mol-K)
Zn+2 (aq)
-153.9 kJ/mol
112.1 J/(mol-K)
Cu (s)
0 kJ/mol
33.15 J/(mol-K)
Cu+2 (aq)
64.77 kJ/mol
-99.6 J/(mol-K)
Electromotive series:
Atomic Weights
H 1.008
C 12.011
O 15.998
Ca 40.070
Mn54.938
Fe 55.845
Cu 63.546
Zn 65.39