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HOUR EXAM IIRK
CHEM 103 NOVEMBER 25 2002
NAME:
Key
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EXAM IIRK
NOVEMBER 25 2002
CH 103
DIRECTIONS
• There is only one correct answer to each question unless otherwise noted. Any questions for which more than one response
has been selected will not be counted
• Your score is based solely on the number of questions you answer correctly. It is to your advantage to answer every
question.
 • The best strategy is to arrive at your own answer to a question before looking at the choices. Otherwise, you may be
misled by plausible, but incorrect, responses.
 YOUR SCORE FOR THE SECOND HOUR EXAM WILL BE THE AVERAGE OF YOUR SCORE ON EXAM II &
EXAM IIR, OR YOUR SCORE ON EXAM II, WHICHEVER IS HIGHER.

IF YOU SELECT “NONE OF THE ABOVE” as an answer, write your numerical answer, including units,
next to it.
IF YOU FIND YOURSELF BAULKED BECAUSE THERE IS A PIECE OF INFORMATION YOU DON’T HAVE,
RAISE YOUR HAND. YOU MAY BE ABLE TO BUY THE INFORMATION FOR A POINT.
TAKE A DEEP BREATH AND LET YOUR EYES FOCUS.
RELAX YOUR SHOULDERS
WHEN IN DOUBT CONVERT TO MOLES!
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Key
NAME:
CHEM 103 NOVEMBER 25 2002
Page 2 of 13
INORGANIC NOMENCLATURE:
1. Name, by IUPAC rules, the following compounds:
a. KBrO _______potassium hypobromite___
b. Al(IO2)3
c. AgClO3
____aluminum iodite_____________
__________silver chlorate_____
d. Co(BrO4)3 ______cobalt(II) erbromate_______
e.
P2O5
______diphophorus pentoxide______
5 pts: ____
2. Give formulae for the following compounds:
a. hydrogen peroxide: ______H2O2_______________________
b. carbon monoxide: _____CO_________________
c. Manganese (II) bromite : ___Mn(BrO2)2___________
d. Sulfurous acid: ____H2SO3____________
e. Nitric acid:
___HNO3_____________
5 pts: ____
BONUS: What is the common name for dihydrogen dioxide?
H2O2 hydrogen peroxide.
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HOUR EXAM IIRK
CHEM 103 NOVEMBER 25 2002
NAME:
Key
Page 3 of 13
3. Which statement is true?
a) Carbon dioxide has POLAR bonds.
b) Hydrogen fluoride is a NONPOLAR molecule
c) Fluorine is the LEAST electronegative element.
d) F2 is POLAR
SHORT ANSWER:
4. a. Write the balanced equation for the reaction between
nitric acid and potassium hydroxide:
HNO3 + KOH  H2O + KNO3
H+ + NO3- + K+ + OH-  H2O + NO3- + K+
H+ + OH-  H2O
b. Write the balanced equation for the reaction between
Acetic acid and potassium hydroxide.
CH3COOH + KOH  H2O + CH3COOK
CH3COOH + K+ + OH-  H2O + CH3COO- + K+
CH3COOH + OH-  H2O + CH3COOc. Write the balanced NET IONIC equation for the reaction between
potassium acetate and water
H2O + CH3COOK  CH3COOH + OHH2O + CH3COO- + K+  CH3COOH + OH- + K+
H2O + CH3COO-  CH3COOH + OHd. Write the balanced equation for the reaction between lithium metal and water, producing lithium hydroxide
(aq) and hydrogen gas.
2Li + 2H2O  2LiOH + H2
e. Write the balanced NET IONIC equation for the reaction between
water and water
H2O + H2O  OH- + H3O+
BONUS: Write the net ionic equation for the reaction between magnesium oxide and water.
MgO + H2O  Mg(OH)2
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HOUR EXAM IIRK
CHEM 103 NOVEMBER 25 2002
NAME:
Key
Page 4 of 13
4. In the sulfite ion, SO32-, the oxidation number for S is
(A) - 6
(B) - 4
(C) 0
(D) + 4
(E) + 6
(F) None of the above
S + 3(-2) = -2
5. In the chemical reaction,
Mg (0)  MgO (Mg2+ , O=) Mg oxidized
2Mg + O2  2MgO
O2 (0)  MgO (Mg2+ , O=) O reduced
Which is true?
a.
b.
c.
d.
e.
Magnesium gets oxidized & O2 gets reduced.
Magnesium gets reduced & O2 gets reduced.
Magnesium gets reduced & O2 gets oxidized.
Magnesium gets oxidized & O2 gets oxidized.
Magnesium is a Lewis Acid.
6.
Definition:
OXIDIZED.
In this reaction
OXIDIZING AGENTS GET REDUCED.
REDUCING AGENTS GET
2IO3- + 5Cu + 12H3O+  I2 + 5Cu2+ + 18H2O
Identify the reducing agent:
(A)
(B)
(C)
(D)
(E)
IO3-
IO3- (I = +5)  I2 (0) reduced
Cu (0)  Cu2+ (+2) oxidized
Cu
H3O+
H2O
None of the above.
BONUS: What is the oxidation number of O in KMnO4 (potassium permanganate)?
O is always –2 except in peroxides
K (+1) + Mn + O (4 x –2) = 0  1 + Mn – 8 = 0
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 Mn = +7
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NAME:
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CHEM 103 NOVEMBER 25 2002 Page 5 of 13
7. Draw the Lewis structure of SO2 . Indicate its 3-D shape. (central atom underlined)
6+ 2(6) = 18 e..
:O:
:O:
..
O:
..
S
..
..
O:
S
2 pts for Lewis structure, 2 pts for both LS’s, 1 pt for trigonal shape
8. Which one of these is a Lewis acid but NOT a Bronstead-Lowry acid??
(A) NH4+
(B) H3O+
(C) AlCl3
N
H
H
H
H
O:
H
H
(D) CH3COOH
..
: Cl :
H
..
: Cl
..
Al
The Al atom has room to
accept an addition pair of
electrons but has no
proton H+ to donate
: O:
C
..
Cl :
..
H3C
..
..O
H
9. In the reaction:
H2O + H2O  OH- + H3O+
1r
2r
1p
2p
A. H2O molecule 1r is acting as a Bronstead base.
B. H2O molecule 1r is acting as a Bronstead acid . DONATING H+
C. H2O molecule 2r is acting as a Bronstead acid.
D. H2O molecule 1r is being oxidized.
BONUS: In question 9 above, which species is the conjugate acid of water molecule 2r?
2p
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NAME:
Key
CHEM 103 NOVEMBER 25 2002 Page 6 of 13
10. Which of the following is a weak acid?
(A) Ba(OH)2 strong base
(B) NH3 weak base
(C) NH4+ weak acid
(D) HNO3 strong acid
(E) HI strong acid
11. The formal charge on the  C in the Vitamin B1 carbanion is:
THIS C
:
S
Formal charge = 4 – 2 – ½(6) =
:
:C
C
N
C
R
R
R
(A) +2
(B) +1
(C) 0
(D) -1
(E) -2
BONUS: What is the formal charge on the S in vitamine B1?
FC = 6 – 4 –1/2(4) = 0
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HOUR EXAM IIRK
CHEM 103 NOVEMBER 25 2002
NAME:
Key
Page 7 of 13
12. How many moles of HCl are needed to produce
10.00 Liters of carbon dioxide at STP? Assume that CaCO3 is in excess.
CaCO3(s) + 2HCl(aq)  CaCl2(aq) + H2O(l) + CO2(g)
A
B
C
HCl
CaCO3
MW (g/mol)
36.45
100.1
CaCl2
111.0
CO2
44.01
H2O
18.01
D
0.4462 mol
0.2231 Mol
0.8923 Mol
10.00 Mol
E
None of the above
10.00 L CO2 STP
STP.
(1 mol/22.414 1 L/mol)STP = 0.4462 mol CO2 made @
0.4462 mol CO2 (2 mol HCl/1 mol CO2) =
BONUS: If you had 6.000 M HCl, how many L of HCL would you need to make the 10.00 L
of CO2?
0.8923 mol HCl needed ( 1 L/6.000 mole HCl) = 0.1487 L of 6 M HCl (148.7 mL)
Page 7 of 13
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CHEM 103 NOVEMBER 25 2002
NAME:
Key
Page 8 of 13
13. Fuel cells burn Hydrogen gas, and produce virtually no pollution:
2H2(g) + O2(g)  2 H2O (l)
Calculate the volume of H2 gas at 76000.0 Torr and 15.0 0C needed to produce 360.0 g of
water.
360.0 g H2) (1 mol H2O / 18.0 g) = 20.0 mol H2O
MW (g/mol)
H3
2.01
O2
H2O
32.0
18.0
A
B
0.00621 L
9.45 L
C
0.260 L
D
E
4.72 L
None of the above
20.0 mol H2O (2 mol H2/2 mol H2O) = 20.0 mol H2
PV = nRT => V = nRT/P
T = 15.0 + 273.15K = 288.15 K
P = 76000. torr (1 atm/760 torr) = 100.00 atm
V = 20.0 mol (0.082057 L atm/K mol)(288.15 K)/100.00 atm
14. 25.7 L of Xenon gas is stored at 2660.0 torr. The pressure is changes to 7030.0 torr at
constant temperature. What is the new volume?
A
B
C
D
E
9.72 L
576 L
67.9 L
7390 L
None of the above
P ↑ V↓
25.7 L (2660.0 torr/7030.0 torr) =
BONUS: Calculate the mass of 1 molecule of sulfur dioxide (MW = 64.1 g/mol)
64.1 g/mol(1 mol/6.022 x 1023 molecules) = 1.06 x 10-22 g
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CHEM 103 NOVEMBER 25 2002
15.
Key
Page 9 of 13
A correct statement of Boyle’s Law is: (If you can’t remember what Robert Boyle did, ask
yourself, “Which one of these is true?”)
(A) T = k/V
(B) 1/T = kV
(C) P = 1/T
(D) VP = n
(E) PV = k
16. You have a sealed container containing a mixture of nitrogen gas and hydrogen gas.
The total pressure is 745.0 torr. The pressure of the N2 is 700.0 torr. The pressure of the
H2 is:
(A) 1445.0 torr
PT = PN2 + PH2
(B) 45.0 torr
745.0 torr = 700.0 torr + PH2
(C) 0.980 atm
(D) 1.060 atm
(E) none of the above
17 . Calculate how many molecules of SO2 gas are present in a sealed, 22.4 L container at
760.0 torr and 273.15 K:
A.
0.500 molecules
B. 760.0 molecules
PV = nRT  n = PV/RT
n = 760 torr(1 atm/760 torr)(22.4 L)/0.082057 L atm/K mol)(273.15 K) =
1 mol SO2
C. 1.00 molecules
1 mol SO2 (6.022 x 1023 molecules/mol) =
D. 6.02 x 1023 molecules
E. None of the above.
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NAME:
Key
CHEM 103 NOVEMBER 25 2002 Page 10 of 13
18. NASA uses a balloon filled with He to monitor gamma rays in the upper
atmosphere. The high altitude balloons can make it to an altitude of 4 km above
the earth with a payload of 200-400 kg of instruments.
Conditions at Sulphur Springs CO, where
the balloon is launched:
T = 28.0oC
= 301.15 K
P = 771.0 mm Hg
V=?
Conditions during the flight:
T = -60.0 oC = 213.15 K
P = 5.00 mm Hg
V = 400,000.0 m3
Calculate the volume of the balloon on the ground at Sulphur Springs:
(A) 3665 m3
T↑ V ↑
P↑ V↓
(B) 2.90 x 1010 m3
400000 m3 (301.15K/213.15K) (5.00 mm Hg/771.0 mm Hg)
(C) 1836 m3
(D) -70400 m3
(E) None of the above
19. Elecromagnetic radiation detected bouncing back from Mt Ascutney has a wavelength
of 3.34 x 106 μm. What is the frequency?
A
B
C
D
E
89.5
0.0111
2.99 x 107
8.95 x 107
None of the above
Hz
Hz
Hz
Hz
C = λν  ν = c/λ
λ = 3.34 x 106 μm (1 m/106 μm) = 3.34 m
ν = 2.99 x 108 m/sec /3.34 m)
=
BONUS: True or false: The CO2 molecule is nonpolar.
..
O
..
C
..
O
..
Page 10 of 13
Each bond is polar, but the polarities cancel
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HOUR EXAM IIRK
NAME:
CHEM 103 NOVEMBER 25 2002
Key
Page 11 of 13
20. In another, parallel universe, the charge/mass ratio of a fundamental particle was
measured and found to be + 5.685 x 10-12 coulombs/kg. From this one can conclude
that:
(A) The mass of the particle must be very large and/or the charge must be very
small.
(B) The particle has a net negative charge.
(C) The mass of the particle must be very small and/or the charge must be very
large.
(D) This particle must be a positively charged electron (positron)
21. Calculate the kinetic energy in Joules of 2 molecules of H2 gas at 5.00 K . (MW = 2.00
g/mol).
A. 2.07 x 10-22 J
B. 125 J
C. 6.25 x 10-23 J
D. 500 J
Ek = 3/2(nRT) for an ideal gas
n = 2 molecules( 1 mole/6.022 x 1023 molecules) = 3.32 x 10-24 moles
Ek = 3/2(3.32 x 10-24 moles)( 8.3145 J/mol K)(5.00 K) =
KLAQUE’S BONUS:
Define ELECTRONEGATIVITY.
Electronegativity is a measure of the tendency of a combined atom to attract a shared pair of
electrons to itself. Elements in the upper right-hand corner of the periodic table tend to
be the most electronegative.
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NAME:
Key
CHEM 103 NOVEMBER 25 2002 Page 12 of 13
SPECIAL UNITS & CONVERSION FACTORS
Acceleration due to gravity (g)
Avogadro’s number
Bohr radius
Boltzmann’s constant
Electronic charge-to-mass ratio
Elementary charge
Faraday constant
Gravitational constant (Universal)
Mass of an electron
Mass of a neutron
Mass of a proton
Molar volume of an ideal gas @ STP
Permittivity of vacuum
Planck’s constant
Rydberg constant
Speed of light in vacuo
Universal gas constant
g
No
ao
kB
-e/me
e
F
G
me
Mn
Mp
Vm
εo
h
R∞
c
R
9.80665 m/sec2
6.0221367 x 1023 particles/mol
0.529177249 x 10-10 m
1.380658 x 10-23 J/K
1.75881962 x 1011 C/kg
1.60217733 x 10-19 C
9.6485309 x 104 C/mol
6.67259 x 10-11 m3/kg sec2
9.1093897 x 10-31 kg
1.6749286 x 10-27 kg
1.6726231 x 10-27 kg
22.41410 L/mol
8.854187817 x 10-12 C2/N m2
6.6260755 x 10-34 sec
2.1798741 x 10-18 J
2.99792458 x 108 m/sec
Note the 2 sets of
8.314510 J/mol K
units for R. Select
0.08205783 L atm/K mol
the one with the
units you need.
Fgrav =
-Gm1m2/r2
Felectrostatic = - [1/4πεo] q1 q2/r2
1 N = 1 kgm/sec2
1 J = 1 Nm = 1 kg m2/sec2
Arrhenius Equation: k = Ae-Eact/RT
Formal charge = #valence e- - #nonbonding e- - ½ (#bonding e-)
EK = 3/2(nRT) for an ideal gas
1 atm = 760 torr
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NAME:
CHEM 103 NOVEMBER 25 2002
Key
Page 13 of 13
PERIODIC TABLE OF THE ELEMENTS
1A
1
H
8A
2
He
3
Li
2A
4
Be
3A
5
B
4A
6
C
5A
7
N
6A
8
O
7A
9
F
6.941
9.012
10.81
12.01
14.01
16.00
19.00
20.18
11
Na
12
Mg
5B
6B
7B
15
P
16
S
17
Cl
18
Ar
24.31
4B
14
Si
22.99
3B
13
Al
19
K
20
Ca
21
Sc
22
Ti
23
V
24
Cr
25
Mn
26
Fe
27
Co
39.10
40.08
44.96
47.88
50.94
52.00
54.94
55.85
37
Rb
38
Sr
39
Y
40
Zr
41
Nb
42
Mo
43
Tc
85.47
87.62
88.91
91.22
92.91
95.94
55
Cs
56
Ba
57
La
72
Hf
73
Ta
74
W
132.9
137.3
138.9
178.5
181.0
87
Fr
88
Ra
89
Ac
104
Unq
105
Unp
(223)
226.0
227.0
(261)
58
Ce
1.008
8B
4.003
10
Ne
1B
2B
26.98
28.09
30.97
32.07
35.45
39.95
28
Ni
29
Cu
30
Zn
31
Ga
32
Ge
33
As
34
Se
35
Br
36
Kr
58.93
58.69
63.55
65.39
69.72
72.61
74.92
78.96
79.90
83.80
44
Ru
45
Rh
46
Pd
47
Ag
48
Cd
49
In
50
Sn
51
Sb
52
Te
53
I
54
Xe
(98)
101.1
102.9
106.4
107.9
112.4
114.8
118.7
121.8
127.6
126.9
131.3
75
Re
76
Os
77
Ir
78
Pt
79
Au
80
Hg
81
Tl
82
Pb
83
Bi
84
Po
85
At
86
Rn
183.8
186.2
190.2
192.2
195.1
197.0
200.6
204.4
207.2
209.0
(209)
(210)
(222)
106
Unh
107
Uns
108
Uno
109
Une
(262)
(263)
(262)
(265)
(266)
59
Pr
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
71
Lu
140.1
140.9
144.2
(145)
150.4
152.0
157.3
158.9
162.5
164.9
167.3
168.9
173.0
175.0
90
Th
91
Pa
92
U
93
Np
94
Pu
95
Am
96
Cm
97
Bk
98
Cf
99
Es
100
Fm
101
Md
102
No
103
Lr
232.0
231.0
238.0
237.0
(244)
(243)
(247)
(247)
(251)
(252)
(257)
(258)
(259)
(260)
END OF EXAM!
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