NAME:____________________________
Fall 2013
INSTRUCTIONS:
Student Number:______________________
Chemistry 1000 Midterm #2A
____/ 47 marks
1) Please read over the test carefully before beginning. You should have 6 pages of
questions and a formula/periodic table sheet.
2) If your work is not legible, it will be given a mark of zero.
3) Marks will be deducted for incorrect information added to an otherwise correct
answer.
4) Marks will be deducted for improper use of significant figures and for missing or
incorrect units.
5) Show your work for all calculations. Answers without supporting calculations
will not be given full credit.
6) You may use a calculator.
7) You have 90 minutes to complete this test.
Confidentiality Agreement:
I agree not to discuss (or in any other way divulge) the contents of this exam until after 8pm Mountain Time
on Monday, November 18th, 2013. I understand that breaking this agreement would constitute academic
misconduct, a serious offense with serious consequences. The minimum punishment would be a mark of
0/47 on this exam and removal of the “overwrite midterm mark with final exam mark” option for my grade
in this course; the maximum punishment would include expulsion from this university.
Signature: ___________________________
Course: CHEM 1000 (General Chemistry I)
Semester: Fall 2013
The University of Lethbridge
Date: _____________________________
Question Breakdown
Spelling matters!
Fluorine = F
Flourine =
Fluorene = C13H10
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
Q9
Q10
/3
/5
/3
/4
/5
/5
/5
/8
/4
/5
Total
/ 47
NAME:____________________________
Student Number:______________________
1. Provide the correct name or the correct chemical formula for the following compounds:
[3 marks]
(a) Fe2S3
(b) Silver(I) oxide
(c) CsF
2.
[5 marks]
You have two beakers of water. A pH indicator is added to both beakers. You add sodium metal to one
beaker and sodium chloride to the other.
(a) Write the overall balanced reactions for what is happening in each beaker, including states of matter.
Briefly describe what is happening. [3 marks]
(b) Will the pH change in any of the two beakers? Briefly explain why or why not. [2 marks]
NAME:____________________________
Student Number:______________________
3.
[3 marks]
(a) Draw all valid resonance structures for the sulfate ion (SO42−).
You must show all non-zero formal charges on the appropriate atoms. [2 marks]
(b) What is the average S–O bond order in SO42−? [1 mark]
4.
[4 marks]
(a) Arrange the following elements in order of increasing first ionization energy: F, O, S [2 marks]
(b) Arrange the following ions in order of decreasing ionic radii: Be2+, Li+, Na+ [2 marks]
NAME:____________________________
5.
Student Number:______________________
[5 marks]
(a) Write a balanced chemical equation for the electrolysis of molten lithium chloride (this electrolysis
reaction follows a similar pathway as sodium chloride). Include states of matter. [1 mark]
(b) In an electrolysis experiment involving molten lithium chloride, if 1670 L of chlorine gas is
produced at a temperature of 21.50 °C and a pressure of 1.00 bar (100 kPa), what mass of lithium
is also produced? Report your answer in kg. [4 marks]
NAME:____________________________
Student Number:______________________
6.
[5 marks]
Complete the following table, giving the name and symbol for an element meeting each description.
Description
Symbol
Name
The element in Group 16 with the smallest
atomic radius
The element in the 3rd period with the largest
enthalpy of electronic attraction
A transition metal that, when neutral, has eight
valence electrons
The element in the 2nd period with the lowest
ionization energy
The element in the 4th period whose most
common ion is a dianion
7.
[5 marks]
Are the following statements correct or incorrect? If incorrect, briefly explain or provide an example
that proves the statement is false.
(a) Lithium metal reacts with elemental nitrogen. [1 mark]
(b) Na+ is highly reactive and does not occur in nature. [1 mark]
(c) Magnesium carbonate decomposes and releases O2 gas when heated. [1 mark]
(d) The reactivity of group 2 metals (alkaline earth metals) increases with increasing mass. [1 mark]
(e) All salts of group 2 metals are soluble in water. [1 mark]
NAME:____________________________
Student Number:______________________
8. Consider the following molecules:
[8 marks]
SeF4 and ICl4−
(a) Draw the Lewis structures for both molecules. Include all non-zero formal charges on the
appropriate atoms. [3 marks]
(b) What is the electron group geometry and molecular geometry for both molecules? [3 marks]
(c) Do these species have a dipole moment? If so, indicate the overall molecular dipole moment
with an arrow which points in the direction of the negative pole. [2 marks]
NAME:____________________________
9.
Student Number:______________________
[4 marks]
Write a balanced chemical equation for each of the following reactions. Include states of matter. If no
reaction occurs, write “NO REACTION” instead.
(a) Beryllium oxide is added to water
(b) Barium metal reacts with oxygen
(c) Calcium carbonate is added to hydrochloric acid
(d) Aluminum metal reacts with oxygen
10.
(a) Calculate the approximate enthalpy change for the combustion of acetylene
shown below: [4 marks]
[5 marks]
2H–CC–H(g) + 5O2(g) —> 4CO2(g) + 2H2O(g)
(b) Is this process exothermic or endothermic? In ten words or less justify your answer. [1 mark]
NAME:____________________________
Student Number:______________________
Some Useful Constants and Formulae
Fundamental Constants and Conversion Factors
Atomic mass unit (u) 1.660 539  10-27 kg
Avogadro's number
6.022 141  1023 mol–1
Bohr radius (a0)
5.291 772  10-11 m
Electron charge (e)
1.602 177  10-19 C
Electron mass
5.485 799  10-4 u
Ideal gas constant (R) 8.314 462 J·mol-1·K-1
8.314 462 m3·Pa·mol-1·K-1
Planck's constant
Proton mass
Neutron mass
Rydberg Constant (RH)
Speed of light in vacuum
Standard atmospheric pressure
Temperature
Volume
6.626 070  10-34 J·Hz-1
1.007 277 u
1.008 665 u
2.179 872 x 10-18 J
2.997 925 x 108 m·s-1
1 bar = 100 kPa
0 K = −273.15 °C
1 cm3 = 1 mL
Formulae
E  h
c  
rn  a0
n2
Z
E  mc2
E n   RH
A
p  mv
Z2
n2
N
t
Bond Dissociation Enthalpy Values
ΔBDH (kJ/mol)
H−H
432
C−H
413
N−H
391
O−H
467
C−C
347
C=C
614
839
CC
C−O
358
C=O
745
N−N
160
N=N
418
O−O
204
O=O
498
Ek 
1 2
mv
2
A  kN

h
p
x  p 
h
4
PV  nRT
N 
ln  2   k t 2  t1 
 N1 
Band of Stability Graph
The graph at the right shows the band of stability.
Stable isotopes are in black. Isotopes that exist but
are not stable are shown in varying shades of gray
with the shades of gray corresponding to different
half-lives.
The original version of the graph used a rainbow colour scale.
http://commons.wikimedia.org/wiki/File:Isotopes_and_half-life_eo.svg
ln 2  k  t1 / 2
NAME:____________________________
1
Student Number:______________________
CHEM 1000 Periodic Table
18
1.0079
4.0026
H
He
2
13
14
15
16
17
6.941
9.0122
10.811
12.011
14.0067
15.9994
18.9984
Li
Be
B
C
N
O
F
Ne
3
22.9898
4
24.3050
5
26.9815
6
28.0855
7
30.9738
8
32.066
9
35.4527
10
39.948
1
2
20.1797
Na
Mg
11
39.0983
12
40.078
3
4
5
6
7
8
9
10
11
12
44.9559
47.88
50.9415
51.9961
54.9380
55.847
58.9332
58.693
63.546
65.39
K
Ca
Sc
Ti
V
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
Br
Kr
19
85.4678
20
87.62
21
88.9059
22
91.224
23
92.9064
24
95.94
26
101.07
27
102.906
28
106.42
29
107.868
30
112.411
31
114.82
32
118.710
33
121.757
34
127.60
35
126.905
36
131.29
Rb
Sr
37
132.905
38
137.327
Cs
Ba
55
(223)
56
226.025
Fr
87
Ra
Y
39
La-Lu
Ac-Lr
88
P
S
Cl
Ar
15
74.9216
16
78.96
17
79.904
18
83.80
Zr
Nb
Mo
Tc
Ru
Rh
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
41
180.948
42
183.85
43
186.207
44
190.2
45
192.22
46
195.08
47
196.967
48
200.59
49
204.383
50
207.19
51
208.980
52
(210)
53
(210)
54
(222)
Hf
Ta
W
Re
Os
Ir
Pt
Au
72
(261)
73
(262)
74
(263)
75
(262)
76
(265)
77
(266)
78
(281)
79
(283)
Rf
Db
Sg
105
106
138.906
140.115
140.908
144.24
La
Ce
Pr
Nd
57
227.028
58
232.038
59
231.036
60
238.029
Ac
Si
14
72.61
40
178.49
104
89
25
(98)
Al
13
69.723
Th
90
Pa
91
U
92
Bh
107
Hs
Mt
Dt
Hg
Tl
Pb
Bi
Po
At
80
81
82
83
84
85
174.967
Rg
108
109
110
111
(145)
150.36
151.965
157.25
158.925
162.50
164.930
167.26
168.934
173.04
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
61
237.048
62
(240)
63
(243)
64
(247)
65
(247)
66
(251)
67
(252)
68
(257)
69
(258)
70
(259)
71
(260)
Np
93
Pu
94
Am
95
Cm
96
Bk
97
Cf
98
Es
99
Fm
100
Md
101
No
102
Developed by Prof. R. T. Boeré
Lr
103
Rn
86