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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
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NAME:______________________________
EXAM IR KEY
OCTEBER 5 2001
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.

IF YOU SELECT “NONE OF THE ABOVE” as an answer, write your numerical answer, including units,
next to it.
 YOUR SCORE FOR THE 1st HOUR EXAM WILL BE EITHER THE AVERAGE OF YOUR SCORE ON EXAM I &
EXAM IR, OR YOUR SCORE ON EXAM I, WHICHEVER IS THE HIGHER.
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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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
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NAME:______________________________
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HOUR EXAM I
NAME:______________________________
CHEM 103 SEPTEMBER 26 2001
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INORGANIC NOMENCLATURE:
1. Name, by IUPAC rules, the following compounds:
a. sodium carbonate
b. sulfuric acid
______Na2CO3 _____________________________
____H2SO4____________________________
c. iron (III) sulfide
___Fe2S3___________________________
d.
potassium hydroxide ___KOH______________________________
e.
disulfur pentoxide
__S2O5_______________________________
5 pts: ____
2. Give formulae for the following compounds:
a. CoSO3: ____Cobalt (II) sulfite_____________________________
b. N2O: ________Dinitrogen monoxide________________
c. HI: _Hydroiodic acid or Hydrogen iodide______________________
d. NaF: __Sodium Fluoride___________________
e. Ba(OH)2:
__Barium hydroxide_________________
5 pts: ____
SHORT ANSWER:
1. DEFINE
“ELECTRONEGATIVITY”:________________________________________________
The measure of the tendency of a combined atom to attract a shared pair of electrons to
itself
10
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
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SHORT ANSWER:
NAME:______________________________
2. Draw the Lewis dot structure of the phosphate ion. Include resonance structures if
appropriate. Predict the 3-D shape of the ion.
3PO4 5 + 4(6) + 3 = 32 e-
MULTIPLE CHOICE PORTION (Each question is weighted at 5 points):
3. The force of electrostatic attraction between a phosphate ion and an aluminum ion is
measured and found to be 2.077 x 10-13 N. Calculate the distance by which these two
ions are separated:
A
B
C
D
E
1.519E-14 m
-1.000E-07 m
4.315E-40 m
1.000E-07 m
None of the above
4. Which is FALSE about
a.
b.
c.
d.
e.
f.
g.



and 
They contain 56 & 57 neutrons respectively;
They contain 42 protons, respectively;
They are the elements Californium and Einsteinium;
  has two (2) MORE electrons than 


They are the element molybdenum;
c and d are both false;
b and e are both false.
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HOUR EXAM I
NAME:______________________________
CHEM 103 SEPTEMBER 26 2001
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BONUS: True or false…all isotopes of carbon are radioactive.
5. A Helium nucleus, He2+, or -particle is produced when 222Rn decays. If it travels at
0.250 times the speed of light, calculate its kinetic energy. Atomic Wt He = 4.0026 g/mol
A
B
C
D
E
1.65E-45 gcm2/sec2
1.86E-04 kgm2/sec2
1.86E-11 kgm2/sec3
1.12E+20 kgm2/sec4
None of the above
6. The correct Lewis structure for the barium ion is:
A.
Ba2+
B.
C.
D.
E.
7. The barium ion is isoelectronic with (has the same # of electrons as):
A. Radon
B. Cesium ion
C. Strontium
D. Lanthanum
E. Krypton
BONUS: How many valence electrons do the ALKALI METALS have?
ONE
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HOUR EXAM I
NAME:______________________________
CHEM 103 SEPTEMBER 26 2001
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8. If the nucleus of an atom were about the size of a softball, the electrons, proportionally,
would likely be found:
a) Within the softball
b) Within a foot of the nucleus;
c) Somewhere in this room;;
d) Somewhere between here and Winooski (about 2-3 km).
e) Somewhere between here and Miami, FL.
9. Which of the following is MOST LIKELY to be an IONIC compound?
A.
B.
C.
D.
Cesium chloride
Sodium dicalcium
Nitrogen trioxide
Methane (CH4)
10. Which of the following is LEAST electronegative?
A. Fluorine
B. Hydrogen
C. Francium
D. Radon
11. A bright green ionic solid in an industrial stain remover is taken to the lab and
analysed:
ELEMENT
Titanium
Sulfur
Oxygen
%
24.95%
25.05%
50.00%
ATOMIC WEIGHT (g/mol)
47.867 g/mol
32.066 g/mol
15.9994 g/mol
The chemical formula is:
A.
B.
C.
D.
TiSO2
Ti2S3O12
Ti4S4O8
Ti12S8O8
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
Page 7 of 14
NAME:______________________________
12. The % by mass Cl in sodium chloride (NaCl) is:
Atomic Wt Na = 22.99 g/mole
Atomic Wt Cl = 35.5 g/mol
HINT: (When in doubt, convert from moles to grams)
A
B
C
D
E
35.5 %
64.8 %
60.7 %
154.4 %
None of the above
BONUS: Which of the following has the HIGHEST % by mass Cl?
A. HCl
B. KCl
C. CsCl
13. Consider the reaction:
Cu(s) + 4HNO3(aq)  Cu(NO3)2(aq) + 2NO2(g) + 2H2O(l)
If you start with 0.0200 g of copper metal and excess nitric acid, how many grams of
copper(II)nitrate will you be able to make?
Molecular & atomic weights:
Cu
Nitric acid
Copper(II) nitrate
Nitrogen dioxide
water
A
B
C
D
E
63.5
63.0
187.6
46.0
18.0
g/mol
g/mol
g/mol
g/mol
g/mol
2.00E-02 g
5.91E-02 g
1.07E-04 g
1.27E+00 g
None of the above
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
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14. Consider the reaction:
SalH + Ac2O  AcSal + HAc
NAME:______________________________
O
O
C
C
C
C
C
C
C
O
C
O
H
+
CH 3
C
O
CH 3
O
H
O
C
C
C
C
C
C
H
O
O
+
C
C
O
H3C
H
O
C
O
CH 3
If you start with 2.0010 g of salicyclic acid (SalH), how many grams of acetic anhydride
(Ac2O) will you have to use to react with it completely?
MW (g/mol)
salicylic acid
acetic anhydride
acetyl salicylic acid
A
B
C
D
E
138.12
102.09
180.16
2.71 g
204 g
0.74 g
1.48 g
None of the above
BONUS: How many significant figures are you allowed in the above problem?
FIVE
15. Elements in Group VII of the periodic table:
a) Tend to lose a single valence electron;
b) Tend to gain two valence electrons;
c) Have filled valence shells;
d) Explode on contact with water.
e) Are diatomic
BONUS: Group VII elements are called:
A. Chalcogens; B. Halogens
C. Alkaline Earth Metals
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
Page 9 of 14
NAME:______________________________
15. The shape of the water (H2O) molecule is:
A. Linear
B. Bent at 90o
C. Bent at 109o (Tetrahedral) D. Bent at 120o (Trigonal planr)
16. Consider the molecule CO.
NAME IT:
A. Carbon (IV) oxide
B. Carbon monoxide
monooxygen
C. Carbon (II) oxide
D. Carbon
17. Still considering CO, the electrons in the CO bond:
A. Spend more time closer to O than C
B. Spend equal time with C and O
C. Spend more time closer to C than O
D. CO is ionic, the electrons spend all their time with C and no time with O
E. CO is ionic, the electrons spend all their time with C and no time with C
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
Page 10 of 14
NAME:______________________________
For Q 18-19, consider the reaction:
3BaCl2 + 2Na3PO4  Ba3(PO4)2 + 6NaCl
Suppose you start with 50.0 mmoles of barium chloride and 50.0 mmoles of sodium
phosphate.
18. Which is the limiting reagent?
A. BaCl2
B. Na3PO4
C. Ba3(PO4)2
D. NaCl
19. How many mmoles of sodium chloride will you make?
A
B
C
D
E
100 mmoles
180 mmoles
50 mmoles
250 mmoles
None of the above
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
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20-21. Consider the reaction:
NAME:______________________________
2CH3NHNH2 + 5O2  2CO2 + 6H2O + 2N2
9.21 g of CH3NHNH2 reacts with 32.0 g of O2.
MW
(g/mol)
mass
(g)
CH3NHNH2
46.1
g/mol
9.2
g
O2
32.0
g/mol
32.0
g
CO2
44.0
g/mol
H2 O
18.0
g/mol
N2
28.0
g/mol
20. Which is the limiting reagent?
A.
CH3NHNH2
B.
O2
C
CO2
D.
H2O
E.
N2
21. How many grams of H2O will you make?
A.
B.
C
D.
E.
0.200 g
41.2 g
10.8 g
21.6 g
none of the above
Bonus: Considering Q 20-21, if you actually manage to make 9.0 g of water in the lab, what
is the % yield?
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
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END OF EXAM!
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NAME:______________________________
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HOUR EXAM I
NAME:______________________________
CHEM 103 SEPTEMBER 26 2001
Page 13 of 14
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
Arrhenius Equarton
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 10-27 J sec
2.1798741 x 10-18 J
2.99792458 x 108 m/sec
8.314510 J/mol K
0.08205783 L atm/K mol
k = Ae-Eact/RT
Fgrav = -Gm1m2/r2
Felectrostatic = - [1/4πεo] q1 q2/r2
1 N = 1 kgm/sec2
1 J = 1 Nm = 1 kg m2/sec2
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HOUR EXAM I
CHEM 103 SEPTEMBER 26 2001
Page 14 of 14
NAME:______________________________
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
44
Ru
85.47
87.62
88.91
91.22
92.91
95.94
(98)
55
Cs
56
Ba
57
La
72
Hf
73
Ta
74
W
75
Re
132.9
137.3
138.9
178.5
181.0
183.8
87
Fr
88
Ra
89
Ac
104
Unq
105
Unp
106
Unh
(223)
226.0
227.0
(261)
(262)
58
Ce
59
Pr
140.1
90
Th
232.0
1.008
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
45
Rh
46
Pd
47
Ag
48
Cd
49
In
50
Sn
51
Sb
52
Te
53
I
54
Xe
101.1
102.9
106.4
107.9
112.4
114.8
118.7
121.8
127.6
126.9
131.3
76
Os
77
Ir
78
Pt
79
Au
80
Hg
81
Tl
82
Pb
83
Bi
84
Po
85
At
86
Rn
186.2
190.2
192.2
195.1
197.0
200.6
204.4
207.2
209.0
(209)
(210)
(222)
107
Uns
108
Uno
109
Une
(263)
(262)
(265)
(266)
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
71
Lu
140.9
144.2
(145)
150.4
152.0
157.3
158.9
162.5
164.9
167.3
168.9
173.0
175.0
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
231.0
238.0
237.0
(244)
(243)
(247)
(247)
(251)
(252)
(257)
(258)
(259)
(260)
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8B
4.003
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