Version A
Team Copy
Chemistry 100: Midterm Exam Practice

Expect the exam to be a cross between:
o questions like these (taken from Fall 2002 & Winter 2003 Exams),
o questions on the Team Exercises, and
o homework problems.
Team Name: _______________________
Leader:
____________________
Worker:
____________________
Recorder:
____________________
Worker:
____________________
Spokesperson: ____________________
Worker:
____________________
1
1
H
H
Atomic Number
Symbol
Atomic Mass
Pauling’s Electronegativity
2
1.008
1.008
2.1
3
2.1
4
5
6
7
8
9
10
Li
Be
B
C
N
O
F
Ne
6.941
9.012
10.81
12.01
14.01
16.00
19.00
20.18
1.0
11
1.5
12
2.0
13
Al
2.5
14
Si
3.0
15
P
3.5
16
S
4.0
17
Cl
26.98
28.09
30.97
32.07
35.45
1.5
1.8
2.1
2.5
3.0
He
4.003
Na Mg
22.99
24.31
0.9
19
1.2
20
K
Ca
39.10
40.08
0.8
37
1.0
38
Rb
Sr
85.47
87.62
0.8
55
0.9
56
Cs
Ba
132.9
137.3
0.7
87
0.9
88
Fr
Ra
(223)
226.0
*
Lanthanide
Series
†
Actinide
Series
1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f
21
Sc
22
Ti
23
V
24
Cr
25
Mn
26
Fe
27
Co
28
Ni
29
Cu
30
Zn
31
Ga
32
Ge
33
As
34
Se
35
Br
44.96
47.88
50.94
52.00
54.94
55.85
58.93
58.69
63.55
65.39
69.72
72.61
74.92
78.96
79.90
1.8
1.8
2.0
2.4
2.8
39
Y
88.91
40
Zr
91.22
41
Nb
42
Mo
43
Tc
44
Ru
45
Rh
46
Pd
47
Ag
48
Cd
49
In
50
Sn
51
Sb
52
Te
53
I
92.91
95.94
(99)
101.1
102.9
106.4
107.9
112.4
114.8
118.7
121.8
127.6
126.9
1.7
1.8
1.9
2.1
2.5
81
Tl
82
Pb
83
Bi
84
Po
85
At
204.4
207.2
209.0
(209)
(210)
1.8
1.9
1.9
2.0
2.2
68
69
70
71
57
La
72
Hf
73
Ta
138.9
178.5
180.9
*
89
Ac
†
227.0
74
75
76
77
78
W
Re
Os
Ir
Pt
183.9
186.2
190.2
192.2
195.1
197.0
200.6
107
108
109
65
66
67
104
105
Rf
Db Sg
Bh Hs Mt
(261)
(262)
(263)
(262)
(265)
(268)
60
61
62
63
64
58
59
Ce
Pr
140.1
140.9
106
79
80
Au Hg
Nd Pm Sm Eu Gd Tb Dy Ho
144.2
90
91
92
Th
Pa
U
232.0
231.0
238.0
(145)
150.4
152.0
157.3
158.9
93
94
95
96
97
162.5
Er Tm Yb Lu
164.9
167.3
168.9
173.0
175.0
100
101
102
103
98
99
Np Pu Am Cm Bk
Cf
Es Fm Md No
Lr
237.0
(251)
(252)
(260)
(244)
HONClBrIF
(243)
(247)
(247)
(257)
(258)
(259)
18
Ar
39.95
36
Kr
83.80
54
Xe
131.3
86
Rn
(222)
Version A
Team Copy
1. (10 pts) Without referring to any periodic table (including the one on the front page of this
exam, write the first 3 rows of the periodic table including element symbol and atomic
number. You must sign and date the statement to get credit for this problem.
I certify that I did not look at any reference while solving this problem.
Signed: __________________________ Date: ______________
1
H
3
Li
11
Na
4
Be
12
Mg
5
B
13
Al
6
C
14
Si
7
N
15
P
8
O
16
S
9
F
17
Cl
2
He
10
Ne
18
Ar
2. (2 pts) Which of the following changes is/are endothermic for the underlined object?
i. baking a potato
ii. a person being burned by a pan
iii. a wood log burning
iv. a lit light bulb shining
v. a person digesting food
A. iii only
B. iii and iv
C. iii and iv
D. i and iv
E. i and ii
3. (2 pts) Which of the following are elements?
i. KOH
iv. carbon tetrachloride
ii. Ne
v. calcium
iii. CO
A. i, ii, and iii
B. iv and v
C. ii and iii
D. ii and v
E. ii, iii, and v
Version A
4. (2 pts) Which of the following is not a particulate sample of matter?
A. An oxygen molecule
B. A human egg cell
C. An electron
D.
E.
Team Copy
A nickel atom
A hemoglobin molecule
5. A chemistry instructor puts some Iodine crystals (I2 (s)) in a flask. Upon warming the flask,
a purple cloud appears.
a. (5 pts) Write the chemical equation that describes this
process.
Heat
I2 (s) + Heat  I2 (g)
or
I2 (s) ----------> I2 (g)
b. (5 pts) Later, an ice cube was held next to the top edge
of the flask. What happened?
Ice
Purple
Cloud
Crystals formed on the edge of the glass.
c. (5 pts) Write the equation for the process from (b).
I2 (g) - Heat  I2 (s)
I2 (g)
 I2 (s) + Heat
I2 (s)
or
d. (5 pts) Which of the processes was endothermic for the Iodine? Briefly describe why.
I2 (s) + Heat  I2 (g)
heat went into the iodine
6. (2 pts) Which of the following properties is/are classified as physical?
i.
ii.
iii.
iv.
v.
the odor of glass cleaning solution
the color of chlorine gas
the electrical conductivity of copper wire
the ability of milk to sour
a compound does not react with bromine
A. i only
B. ii only
C. i and ii
D.
E.
i, ii, and iii
iv and v
7.
Version A
(2 pts) Which of the following properties is/are classified as chemical?
i.
ii.
iii.
iv.
v.
the taste of honey
the ability of hair to stretch
the corrosive character of hydrochloric acid
the combustibility of ethanol
the softness of talc
A. i and ii
B. i, ii, and v
C. iii only
8.
iv only
iii and iv
i only
ii only
iv only
D.
E.
i and iv
i, ii, and iv
(2 pts) In which of the following pairs of substances will there be a net attractive
electrostatic force?
A.
B.
C.
D.
E.
10.
D.
E.
(2 pts) Which of the following substances is/are homogeneous?
i.
mineral oil
iv.
sugar
ii.
a plant leaf
v.
freshly squeezed lemonade
iii.
sausage
A.
B.
C.
9.
Team Copy
Two positively charged table tennis balls
A negatively charged piece of dust and a positively charged piece of dust
A positively charged sodium ion and a positively charged potassium ion
A negatively charged chloride ion and a negatively charged bromide ion
Two negatively charged pith balls
(2 pts) One of the main features of Dalton's atomic theory which is no longer considered
valid is: All atoms of each element are identical in every respect. Which of the following is
the best explanation of why this feature is no longer considered valid?
A.
B.
C.
D.
The existence of isotopes
Mass is conserved in a chemical change
Nearly all of the mass of an atom is concentrated in the nucleus
The total charge of the electrons of an atom exactly balances the positive
charge of the nucleus
E. The planetary model of the atom has been shown to be incorrect
11.
Version A
Team Copy
(2 pts) Which of the three major subatomic particles has/have a charge of +1?
Proton
12.
41
K
(2 pts) The nuclear symbol of an isotope of potassium is 19 . Indicate the number of
protons, number of neutrons, atomic number, and mass number of the isotope.
Number of protons
13.
Number of neutrons
Atomic number
Mass number
A. 19
22
19
41
B.
22
19
41
19
C.
19
41
19
22
D. 41
19
22
19
E.
19
41
22
41
(2 pts) Which of the three major subatomic particles has/have a mass of approximately one
amu?
proton, neutron
14.
(3 pts) Isotopes of an element vary in mass because of differing numbers of:
neutrons
15.
(5 pts) Write the elemental formula for the following elements:
Element
Elemental Formula
i.
nitrogen
N2
ii.
sulfur
S
iii.
lithium
Li
iv.
bromine
Br2
v.
oxygen
O2
16.
Version A
Team Copy
(3 pts). The alkali metal kalium was discovered in 1807. What is its English name and
symbol?
Potassium
17.
(10 pts) Neatly sketch and label the apparatus/experiment that disproved the Plum Pudding
model of the atom.
Rutherford experiment
18.
Early chemists classified the elements by their chemical properties and gave these groups of
elements special names.
a. (3 pts) What feature of the periodic table do these groups correspond to?
columns
b. (3 pts) Write the names of three of these groups.
alkali metals, alkaline earths, transition metals, halogens, noble gases
c. (0 pts) Choose one of the following elements and circle it.
(Read d – f before making your choice!)
Calcium
Cobalt
Chlorine
d. (3 pts) Write the electronic configuration of that element:
Calcium:
Cobalt:
Chlorine:
1s22s22p63s23p64s2
1s22s22p63s23p64s23d7
1s22s22p63s23p5
(easiest one!)
e. (3 pts) Write the name of the group that the element belongs to:
Calcium:
Cobalt:
Chlorine:
alkaline earths
transition metals
halogens
f. (2 pts) How many electrons are your element’s valence (outer shell)?
Calcium:
Cobalt:
Chlorine:
2
2
7
19.
Version A
Team Copy
The element bromine (name for the Greek word for stench, brômos) was discovered in 1826
by Antoine J. Balard.
a. (3 pts). Write its electronic configuration.
1s22s22p63s23p64s24d104p5
On the figure below:
b. (3 pts). Label the s, p, and d orbitals.
c. (2 pts). Fill in electrons for Bromine in the energy level diagram.
s
E
p
d
4d
5
5s
5p
4
4s
4p
3s
3p
3d
3
Either labeling the top & side (w/ special label for
3d, 4d. or labeling each set of orbitals is ok.
2
2s
2p
d. (2 pts). Bromine has two stable isotope with masses 79 and 81. Write the nuclear symbol
for these isotopes.
79
Br
35
81 1
d
Br
35
1s
d
20.
Version A
Team Copy
(6 pts) A dedicated Chemistry 100 student tried to repeat the paper chromatography
experiment from lecture. Based on the individual results, Label each of the following
samples as homogenous, heterogeneous, or undetermined.
Sample:
Fluid:
Black Sharpie
Black Marker
(Permanent)
Blue Overhead
Pen
Water
Rubbing Alcohol
Water
Resulting Paper:
Sample Type: (homogenous/
heterogeneous/ undetermined)
homogenous/
or
undetermined
heterogeneous
heterogeneous