CHM 134 General Chemistry I
Quiz 2, Fall 2009 – Drs. Foy and Steel
Name SOLUTIONS
1. (3 points) What is the correct symbol for each of these elements?
phosphorus
P
magnesium
Mg
neon
Ne
manganese
Mn
iron
Fe
carbon
C
2. (3 points) Name each of these elements.
B
boron
Cr
chromium
Br
bromine
Cu
copper
S
sulfur
K
potassium
3. (1 point) Write the complete chemical symbol for an atom of an element that has 28 protons
and 31 neutrons.
4. (1 point) What is the identity of the element described by the chemical symbol
72
32
X?
germanium, Ge
5. (1 point) Circle the two atoms in the group below that have the same number of neutrons.
64
28
Ni
63
29
Cu
64
30
Zn
68
30
Zn
6. (1 point) Circle the two atoms in the group below that are isotopes.
45
21
Sc
48
22
Ti
50
22
Ti
50
23
V
7. (3 points) Circle the three elements in the group below that are likely to have similar
chemical and physical properties.
aluminum
lithium
magnesium
neon
potassium
sodium
8. (1 point) Name the halogen that has the lightest atomic mass.
Fluorine, F
9. (1 point) To which group does magnesium belong?
alkaline earth metals
10. (2 points) What are the name and symbol of the fourth element in the fourth period on the
periodic table?
titanium, Ti
11. (3 points) Complete the table by indicating the number of each type of subatomic particle in
each of these atoms and ions.
Symbol
protons
30
53
neutrons
37
73
electrons
30
54
12. (5 points) Bromine has two naturally occurring isotopes. The weighted average atomic mass
of bromine is 79.904 amu. If 50.54% of bromine is found as bromine-79 (78.9183 amu),
what is the mass of the other isotope?
This equation uses the percent abundance in their decimal forms. This could also be set up
with the regular percentage, but you would have to multiply the right by 100.
(78.9183)(0.5054) + x(1 − 0.5054) = 79.904
39.8853 + 0.4946x = 79.904
0.4946x = 40.0187
x = 80.91 u
13. (5 points) Convert 2.75
2.75
to
.
3600
1
2.54
1
1
100
0.162