Download Chemistry 2100 In-Class Test 1(A)

NAME:____________________________
Summer 2006
INSTRUCTIONS:
1.
Student Number:______________________
Chemistry 1000 In-Class Test #1
____/ 50 marks
1) Please read over the test carefully before beginning. You should have
6 pages of questions, and a formula/periodic table sheet (7 pages total).
2) If your work is not legible, it will be given a mark of zero.
3) Marks will be deducted for improper use of significant figures and for
missing or incorrect units.
4) Show your work for all calculations. Answers without supporting
calculations will not be given full credit.
5) You may use a calculator.
6) You have 50 minutes to complete this test.
Give the name and symbol for one element that meets each description.
Symbol
exists primarily as diatomic molecules
reacts vigorously/violently with water
chalcogen in the third period
gaseous halogen (at room temperature)
smallest atomic radius (for a neutral atom)
has 8 protons, 8 neutrons and 8 electrons
transition metal that can make a +3 cation
gains two electrons to make a stable ion
neutral atom (in the ground state) has the
electron configuration:
1s22s22p63s23p2
its highest energy electron (in the ground state)
has the following quantum numbers:
n = 4, l = 0, ml = 0, ms = +½
Name
[10 marks]
NAME:____________________________
2.
Student Number:______________________
A magnesium atom has two valence electrons with the following quantum numbers:
n = 3, l = 0, ml = 0, ms = +½
and
n = 3, l = 1, ml = 0, ms = -½
[4 marks]
(a)
Is this atom in the ground state or in an excited state?
(b)
Justify your answer to part (a).
3.
[9 marks]
(a)
Complete the following table using shorthand notation for the electron configurations.
(i.e. Do not use noble gas notation for core electrons.)
Symbol
Electron Configuration
Number of
Valence Electrons
Mn
Sn
(b)
Use the noble gas abbreviation to write the electron configuration for tin (Sn).
(c)
Draw an orbital box diagram showing the valence electrons of tin. Label each box.
(d)
Is tin paramagnetic or diamagnetic? In ten words or less, justify your answer.
NAME:____________________________
4.
Student Number:______________________
(a)
For each of the questions below, justify your answer in terms of atomic structure.
[4 marks]
Which has a higher electron affinity, nitrogen or neon?
(b)
Which has a larger radius, Cl or Cl ?
5.
Complete the following table. For each orbital,
(a)
Draw a sketch including a set of axes to clearly show the orbital’s orientation;
(b)
Give one set of valid quantum numbers;
(c)
Indicate the total number of nodes; and
(d)
Indicate the number of planar nodes (also called “nodal surfaces”).
-
Orbital
6 px
4d z 2
Sketch
n
l
ml
[7 marks]
nodes
total
planar
NAME:____________________________
Student Number:______________________
6.
A hydrogen atom is in the ground state. It absorbs a photon of electromagnetic radiation
and is excited into the n = 3 state.
[8 marks]
(a)
Calculate the energy of the photon absorbed.
(b)
Calculate the wavelength (in nm) of the photon absorbed.
(c)
If a Li2+ ion were to undergo the same transition (ground state to n = 3), would the energy
of the photon absorbed be higher, lower or the same (compared to the one absorbed by
hydrogen)? Based on the structure of the ion, briefly explain why this is.
You do not need to perform/show any calculations for this part of the question.
NAME:____________________________
7.
Student Number:______________________
Naturally occurring thallium consists of two isotopes. The more abundant isotope
(70.476%) is 205Tl which has a mass of 204.9744 u. Calculate the mass of an atom of the
less abundant isotope of thallium.
[4 marks]
NAME:____________________________
Student Number:______________________
8.
A bottle contains 4.00 L of chloroform (CHCl3; density = 1.492 g/mL).
(a)
Calculate the mass of chloroform in the bottle.
(b)
Calculate the number of atoms of chlorine in the bottle.
[4 marks]
NAME:____________________________
Student Number:______________________
Some Useful Constants and Formulae
Fundamental Constants and Conversion Factors
Atomic mass unit (u)
1.6605 × 10-24 g
Avogadro's number
6.02214 × 1023 mol–1
Bohr radius
5.29177 × 10-11 m
Coulomb constant
8.998 × 109 N·m2·C-2
Electron charge (e)
1.6022 × 10-19 C
Electron mass
5.4688 × 10-4 u
6.626 × 10-34 J·s
1.0072765 u
1.0086649 u
1.097 x 107 m-1
2.179 x 10-18 J
2.9979 x 108 m·s-1
Planck's constant
Proton mass
Neutron mass
Rydberg Constant (R)
Rydberg unit (Ry)
Speed of light in vacuum
Formulae
v = υλ
E = hυ
υ
λ
(often, c =
)
d =
m
V
M =
2
rn = a 0 n
Z
m
n
F = k
λ = h
ρ
∆x . ∆ρ >
Z2
n2
En = -1 Ry
1
(n+e)(n-e)
d2
ρ = mv
h
4π
E = k
(n+e)(n-e)
d
= R
1 - 1
n12
n22
1
λ
1 - 1
n 22
n12
∆E = En2 - En1 = Ry . Z 2
Chem 1000 Standard Periodic Table
18
4.0026
1.0079
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
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)
107
Np
93
Pu
94
Am
95
Cm
96
Rn
86
Bk
97
Cf
98
Es
99
Fm
100
Md
101
No
102
Lr
103
Developed by Prof. R. T. Boeré