Chapter 4 Review Worksheet.
Name ___________________________
Period _______ Date ______________
True-False Classify each of the following statements as always true, AT; sometimes true, ST;
or never true, NT.
NT__ 1. According to Dalton’s atomic theory, atoms are composed of protons, electrons, and
neutrons.
__ST___ 2. Atoms of elements are electrically neutral.
__NT___ 3. The mass of an electron is equal to the mass of a neutron.
__AT___ 4. The charge on all protons is the same.
__NT___ 5. The atomic number of an element is the sum of the protons and electrons in the
atom.
__NT___ 6. The atomic number of an element is the whole number that decreases as you read
across each row of the periodic table from left to right.
__ST___ 7. An atom of nitrogen has 7 protons and 7 neutrons.
__AT___ 8. Relative atomic masses are measured in amus.
__AT___ 9. The number of neutrons in the nucleus can be calculated by subtracting the atomic
from the mass number.
10. Complete the following table.
Element
Symbol
Atomic
Mass
Number of Number of Number of
Number
Number
Protons
Electrons
neutrons
Carbon
C
6
12
6
6
6
Potassium
K
19
2
19
19
21
Magnesium
Mg
12
24
12
12
12
Helium
He
2
4
2
2
2
Boron
B
5
11
5
5
6
11.Complete the following table
Element
Symbol
Number of
Protons
Manganese
Mn
25
Sodium
Na
11
Bromine
Br
35
Yttrium
Y
39
Arsenic
As
33
Actinium
Ac
89
12. Fill in the following Table
Element
Symbol
nitrogen-15
Neon-22
15
7N
N
Number of
electrons
25
11
35
39
33
89
Atomic
Number
7
22
10 Ne
10
Number of
neutrons
28
12
45
50
42
138
Mass
Number
15
22
Atomic
Number
25
11
35
39
33
89
Mass
Number
53
23
80
89
75
227
Number of
neutrons
8
12
Beryllium-9
9/4 Be
4
9
5
13. Use the following information to determine the atomic mass of chlorine. Two isotopes are
known: chlorine-35 (mass = 35.0 amu) and chlorine-37 (mass = 37.0 amu). The relative
abundance’s are 75.4% and 24. 6%, respectively. 39.492 amu
N
14. Use the following information to determine the atomic mass of carbon. Two isotopes are
known: carbon-12 (mass = 12.00 amu) and carbon-13 (mass = 13.00 amu). Their relative
abundance’s are 98.9% and 1.10% respectively.12.011amu
15
7
15. Given the relative abundance of the following naturally occurring isotopes of oxygen,
calculate the average atomic mass of oxygen: 16.005 amu
oxygen- 16: 99.76%
oxygen- 17: 0.037%
oxygen-18: 0.204%
16. Distinguish between protons, electrons, and neutrons in terms of their relative masses and
charges .
Protons- Mass = 1
Charge= +1
Neutrons- Mass = 1
Charge= -0
Electrons- Mass = 1/1840 Charge= -1
17. Discuss the structure of an atom including the location of the proton, electron, and neutron
with respect to the nucleus.
Electrons- area surrounding the nucleus
Proton- In the nucleus
Neutron- In the nucleus
18. Summarize Dalton’s atomic Theory
All matter is composed of atoms
All atoms of a given element are identical, not having the same size mass or chemical
properties.
Atoms of a specific element are different from those of any other element.
Atoms cannot be changed
Atoms combine in simple whole number ratios to form compounds
A chemical reaction is when atoms are separated, combined, or rearranged.