Unit 3 Test
1. A particle of matter contains 6 protons,
7 neutrons, and 6 electrons. This
particle must be a
A |
neutral nitrogen atom |
C |
positively charged
carbon ion |
B |
neutral carbon atom |
D |
positively charged
nitrogen ion |
2. The mass number of an atom is always
equal to the total number of its
A |
protons only |
C |
electrons plus
protons |
B |
electrons only |
D |
protons plus neutrons |
3. What is the approximate mass of an
electron?
A |
1 atomic mass unit |
C |
1/1836 of a
proton |
B |
1/12 of a
C-12 atom |
D |
1836/1837 of a
proton |
4. What is the molar mass of calcium
nitrate, Ca(NO3)2?
A |
164 g/mole |
C |
102 g/mole |
B |
150. g/mole |
D |
70.0 g/mole |
5. What is the total number of atoms in 1
mole of calcium?
A |
1 |
C |
6.02 x 1023 |
B |
40 |
D |
40(6.02 x 1023) |
6. What is the mass (in grams) of 3.0 x 1023
molecules of CO2?
A |
22 g |
B |
44 g |
C |
66 g |
D |
88 g |
7. The major portion of an atom’s mass
consists of
A |
electrons and protons |
C |
neutrons and
positrons |
B |
electrons and
neutrons |
D |
neutrons and protons |
8. Which atom contains exactly 15 protons?
A |
phosphorus – 32 |
C |
oxygen - 15 |
B |
sulfur – 32 |
D |
nitrogen - 15 |
9. Which symbols represent atoms that are
isotopes of each other?
A |
14C and 14N |
B |
131I and 131I |
C |
16O and 18O |
D |
222Rn and 222Ra |
10. Which pair of atoms contains the same number of
neutrons?
A |
11H and 32He |
B |
31H and 32He |
C |
21H and 42He |
D |
31H and 42He |
11. The atomic theory proposed by
A |
has been totally
discarded |
C |
has been accepted
unchanged to the present day |
B |
has been expanded and
modified |
D |
has been found to be
false |
12. As the average atomic masses of the elements on
the Periodic Table increase, the number of atoms in 1 mole of each element
A |
decreases |
B |
increases |
C |
remains the same |
13.
A |
could not combine |
C |
all had the same mass |
B |
could not be created
or destroyed |
D |
were invisible |
14. Element X has two naturally-occurring
isotopes. If the percent abundance of 85X
is 72.0% and the percent abundance of 87X is 28.0 %, the average
atomic mass of element X is equal to
A |
(72.0 x 85) x (28.0 +
87) |
C |
(0.72 x 87) + (0.28 x
85) |
B |
(72.0 - 85) x (28.0 +
87) |
D |
(0.72 x 85) + (0.28 x
87) |
15. How many neutrons does fluorine - 17 have in
its nucleus?
A |
9 |
B |
8 |
C |
7 |
D |
6 |
16. Most of the volume of an atom is made up of the
A |
nucleus |
B |
electron cloud |
C |
neutrons |
D |
protons |
17. The atomic number of neon is 10. The atomic number of calcium is 20. Compared with a mole of neon, a mole of
calcium contains
A |
twice as many atoms |
C |
an equal number of
atoms |
B |
half as many atoms |
D |
20 times as many
atoms |
18. The nucleus of an atom has all of the following
characteristics EXCEPT that it
A |
is positively charged |
C |
contains nearly all
of the atom’s mass |
B |
is very dense |
D |
contains nearly all
of the atom’s volume |
19. Zinc - 66 (atomic number 30) has
A |
30 neutrons |
B |
35 neutrons |
C |
36 neutrons |
D |
96 neutrons |
20. The atomic number of oxygen, 8, indicates that
there are eight
A |
protons in the
nucleus of an oxygen atom |
B |
oxygen isotopes |
C |
neutrons outside the
oxygen atom’s nucleus |
D |
energy levels in the
oxygen atom’s nucleus |
21. An aluminum isotope consists of 13 protons, 13
electrons, and 14 neutrons. Its mass
number is
A |
13 |
B |
14 |
C |
27 |
D |
40 |
22. The mass of 2.50 moles of calcium atoms is
approximately
A |
10.0 g |
B |
100. g |
C |
42.5 g |
D |
250. g |
23. What is the correct number of atomic particles
in a neutral atom with an atomic number of 53 and a mass number of 127?
A |
protons = 53,
electrons = 127, neutrons = 127 |
B |
protons = 53,
electrons = 74, neutrons = 74 |
C |
protons = 127,
electrons = 127, neutrons = 74 |
D |
protons = 53,
electrons = 53, neutrons = 74 |
24. According to the law of conservation of mass,
when sodium, hydrogen, and oxygen react to form a compound, the mass of the
compound is ___ the sum of the masses of the individual elements.
A |
equal to |
C |
less than |
B |
greater than |
D |
either greater than
or less than |
25. An ion with 5 protons, 6 neutrons, and a charge
of +3 has an atomic number of
A |
5 |
B |
6 |
C |
8 |
D |
11 |
Matching
Match the scientist to
his contribution to the development of the atomic theory.
A |
Bohr |
D |
|
B |
Chadwick |
E |
Thomson |
C |
|
|
26. discovered the neutron
27. discovered the electron using a
cathode ray tube
28. postulated that electrons travel
around the nucleus in orbits
29. first published atomic theory; law of conservation of mass
30. discovered the nucleus using the
gold foil experiment
Match the terms below
with their correct definitions.
A |
|
E |
|
B |
|
F |
|
C |
|
G |
|
D |
|
H |
|
31. Isotope in which the number of neutrons is six
more than the isotope’s atomic number
32. Copper-63
33. Copper with seven neutrons more than its atomic
number
34. Isotope that has one neutron more than its
number of protons
35. Carbon with equal numbers of neutrons, protons,
and electrons
36. Carbon with two more neutrons than its number
of protons
37. Chromium with two more neutrons than its number
of protons
38.
Isotope in which the difference between the neutrons and
number of protons is 4