Download Chapter 17 Resource: Properties of Atoms and the Periodic Table

Glencoe Science
Chapter Resources
Properties of Atoms and
the Periodic Table
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Reproducible Student Pages
ASSESSMENT
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✔ Section Focus Activity
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HANDS-ON ACTIVITIES
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✔ Foldables–Reading and Study Skills activity sheet
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MEETING INDIVIDUAL NEEDS
✔ Directed Reading for Content Mastery
✔ Directed Reading for Content Mastery in Spanish
✔ Reinforcement
✔ Enrichment
✔ Note-taking Worksheets
Name
Date
Directed
ContentReading for
MasteryMastery
Content
Class
Overview
Properties of Atoms and the
Periodic Table
Directions: Complete the concept map using the terms in the list below. Terms can be used more than once.
protons
periodic table
electrons
neutrons
have a mass
number equal to
the sum of
are made up of
1.
and
Meeting Individual Needs
Atoms
are organized
as elements in the
5.
4.
2.
and
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
and
6.
3.
Directions: complete the following sentences by underlining the correct words in parentheses.
7. An element is matter that is composed of one type of (atom/quark).
8. The unit of measurement used for atomic particles is the
(atom size/atomic mass unit).
9. Atoms of the same element that have different numbers of neutrons are called
(isotopes/electron clouds).
10. In the periodic table, elements are arranged by increasing atomic (power/number).
11. An electron dot diagram uses the symbol of an element and dots to represent
the (quarks/electrons) in the outer energy level.
Properties of Atoms and the Periodic Table
19
Name
Date
Directed Reading for
Content Mastery
Section 1
■
Section 2
■
Class
Structure of the
Atom
Masses of Atoms
Directions: Use the terms below to complete the following paragraphs about atoms , atomic mass, and
isotopes. Terms may be used more than once.
six
number
electrons
isotopes
electron cloud
neutron(s)
proton(s)
mass
quarks
six protons
The electron has very little mass compared to the 1. ________________ or
many 3. ________________ and 4. ________________ it has. The sum of the
protons and neutrons is the mass 5. ________________ of an atom. The number
of neutrons in an atom can be found by subtracting the atomic number from the
6. ________________ number. The mass of the atom is so small that there is a
measure called the atomic 7. ________________ unit designated by amu.
8. ________________ and 9. ________________ make up the nucleus and are made up
of 10. ________________. There are 11. ________________ uniquely
different quarks. 12. ________________ are found in an area around the nucleus called
the 13. ________________. The nuclei of all atoms of a given element always have the
same number of 14. ________________. They will also have the same number of
15. ________________ around the nucleus. Some atoms may have more or fewer
16. ________________ than will other atoms of the same element. Atoms of the same
element with different numbers of neutrons are called 17. ________________. Every
atom of carbon must contain 18. ________________ but some contain six neutrons and
others have eight neutrons.
20 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
2. ________________. The mass of the atom depends on the nucleus and how
Name
Date
Directed Reading for
Content Mastery
Section 3
■
Class
The Periodic
Table
Periodic Table of the Elements
Key
1
2
3
4
H
Hydrogen
1.008
2
3
4
7
Carbon
12.011
2
13
14
15
16
5
6
7
8
He
17
Helium
4.003
9
10
Li
Be
Beryllium
9.0122
B
C
N
O
F
Ne
Boron
10.81
Carbon
12.011
Nitrogen
14.007
Oxygen
15.999
Fluorine
18.998
Neon
20.180
11
12
13
14
15
16
17
18
Al
Si
P
S
Cl
Ar
Aluminum
26.98
Silicon
28.086
Phosphorus
30.974
Sulfur
32.06
Chlorine
35.453
Argon
39.948
Na
Mg
Sodium
22.990
Magnesium
24.305
3
4
5
6
7
8
9
10
11
19
20
21
22
23
24
25
26
27
28
29
30
Cr
Mn
Fe
Co
Ni
Cu
Zn
Ga
Ge
As
Se
Br
Kr
Iron
55.847
Cobalt
58.9332
Nickel
58.693
Copper
63.546
Zinc
65.39
Gallium
69.72
Germanium
72.61
Arsenic
74.922
Selenium
78.96
Bromine
79.904
Krypton
83.80
K
Ca
Sc
Ti
V
Potassium
39.098
Calcium
40.078
Scandium
44.956
Titanium
47.88
Vanadium
50.94
38
39
40
Sr
Y
Zr
Nb
Strontium
87.62
Yttrium
88.9059
Zirconium
91.224
Niobium
92.91
57
56
La
Cs
Ba
Cesium
132.905
Barium
137.327
Lanthanum
138.906
Chromium Manganese
51.996
54.938
41
Rb
Rubidium
85.468
55
6
C
Lithium
6.941
37
5
18
Atomic number
Element's symbol
Element's name
Atomic mass
6
1
72
42
43
44
Mo
Tc
Ru
Molybdenum Technetium Ruthenium
97.907
101.07
95.94
73
74
75
76
45
47
31
48
32
33
36
49
50
Pd
Ag
Cd
In
Sn
Sb
Te
I
Xe
Palladium
106.42
Silver
107.868
Cadmium
112.41
Indium
114.82
Tin
118.710
Antimony
121.757
Tellurium
127.60
Iodine
126.904
Xenon
131.29
83
52
35
Rh
80
51
34
Rhodium
102.906
77
46
12
84
53
54
78
79
81
82
Hf
Ta
W
Re
Os
Ir
Pt
Au
Hg
Tl
Pb
Bi
Po
At
Rn
Hafnium
178.49
Tantalum
180.95
Tungsten
183.85
Rhenium
186.207
Osmium
190.2
Iridium
192.22
Platinum
195.08
Gold
196.967
Mercury
200.59
Thallium
204.383
Lead
207.2
Bismuth
208.98
Polonium
208.982
Astatine
209.987
85
Radon
222.018
86
87
88
89
104
105
106
107
108
109
110
111
112
114
116
118
Fr
Ra
Rf
Db
Sg
Bh
Hs
Mt
Uun
Uuu
Uub
Uuq
Uuh
Uuo
Francium
223.020
Radium
226.025
Ac
Actinium
227.028
Rutherfordium
(261)
Dubnium
(262)
Seaborgium
(263)
Bohrium
(262)
Hassium
(265)
Meitnerium
(266)
Ununnilium
(269)
Unununium
(272)
Unumbium
(277)
Ununquadium
(285)
Ununhexium
(289)
Ununodium
(293)
Rare-Earth Elements
58
Lanthanide
Series
Ce
Cerium
104.115
90
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Actinide
Series
59
60
61
62
Pr
Nd
Pm
Sm
Praseodymium Neodymium Promethium Samarium
150.36
63
64
Eu
Gd
Europium Gadolinium
151.965
157.25
140.908
144.24
144.913
91
92
93
94
95
Np
Pu
Am
Th
Pa
U
Thorium
232.038
Protactinium
231.036
Uranium
238.029
Neptunium Plutonium Americium
237.048
244.064
243.061
96
Cm
Curium
247.070
65
Tb
Terbium
158.925
66
67
Dy
Ho
Dysprosium Holmium
162.50
164.93
68
69
70
71
Er
Tm
Yb
Lu
Erbium
167.26
Thulium
168.934
Ytterbium
173.04
Lutetium
174.967
97
98
99
100
101
102
Bk
Cf
Es
Fm
Md
No
Berkelium Californium Einsteinium Fermium Mendelevium Nobelium
247.070
251.080
252.083
257.095
259.101
258.099
103
Lr
Lawrencium
260.105
Directions: Use the periodic table above to answer the following questions.
1. List two types of information that are given in each box of this periodic table.
a.
b.
2. In this table, where are the metals located?
3. Where are the nonmetals located?
4. What are the elements in Groups 3 through 12 called?
5. What are the elements called that are next to the stairstep-shaped line on the
right side of the table?
6. What do we call the letter or letters that represents an element?
7. How many elements are included in the modern periodic table?
8. What name is given to the elements in Group 18?
Properties of Atoms and the Periodic Table
21
Meeting Individual Needs
1—New designation
Name
Date
Directed Reading for
Content Mastery
Class
Key Terms
Properties of Atoms and the
Periodic Table
Directions: Match the term in Column II with the definition in Column I. Write the letter of the correct term in
the blank at the left.
Column I
1. sum of the number of protons and
neutrons in the nucleus
3. positively charged center of an atom
4. vertical column in the periodic table
5. neutral particles in the nucleus of an atom
6. weighted average mass of the mixture of
its isotopes
a. nucleus
b. electrons
c. protons
d. neutrons
e. quark
f. atomic number
g. mass number
7. positively charged particles in an atom
8. table of the elements arranged according
to repeated changes in properties
9. represents the electrons in the outer
energy level of an element
h. isotope
i. average atomic mass
j. electron cloud
10. negatively charged particles in an atom
k. periodic table
11. atoms of the same element that have
different numbers of neutrons
l. atom
12. number of protons in an atom’s nucleus
m. atomic mass unit
13. horizontal row in the periodic table
n. group
14. smallest known particle that makes
up protons and neutrons
o. electron dot diagram
15. the smallest peice of matter that still
retains the properties of the element
p. period
16. developed an early periodic chart
17. approximately 1.67 ✕ 10-24g
22 Properties of Atoms and the Periodic Table
q. Dmitri Mendeleev
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
2. region around the nucleus where the
electrons are found
Column II
Name
Date
1
Reinforcement
Class
Structure of the Atom
Directions: Answer the following questions on the lines provided.
1. How is the chemical symbol of an element determined?
Meeting Individual Needs
2. What are atoms composed of?
3. Are electrons, protons, or neutrons the smallest particles? If not, what are?
4. How many types of quarks are there and what is the name of one of them?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
5. Why do scientists use models to study atoms?
6. Why has the atomic model changed over time?
7. Why is the current atomic model called the “Electron Cloud Model”?
Directions: Match the term in Column I with the definition in Column II. Write the letter of the correct definition
in the blank at the left.
Column I
Column II
8. electron
a. positively charged particle
9. neutron
b. negatively charged particle
10. nucleus
c. neutral particle
11. proton
d. smaller particles that make up
protons and neutrons
e. positively charged center of an atom
12. quark
Properties of Atoms and the Periodic Table
27
Name
2
Date
Reinforcement
Class
Masses of Atoms
Directions: Answer the following questions on the lines provided.
1. What are isotopes?
3. What is the average atomic mass of an element?
4. Compare and contrast the atomic structure of the chlorine-35 and chlorine-37 isotopes.
5. Suppose that a newly discovered element called centium has three isotopes that occur in
nature. These are centium-200, centium-203, and centium-209. Assume that these isotopes
occur in equal amounts in nature. What will be the average atomic mass of this element?
28 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
2. How do Boron-10 and Boron-11 differ?
Name
Date
3
Class
The Periodic Table
Reinforcement
Directions: You will need a scientist’s patience to find the names of the 70 elements hidden in the grid. The
lanthanides and the actinides have been excluded. The same letters may appear in more than one element name.
Draw a line through the letters that correctly spell the name of an element.
A Y M R
A S
S M
R N U E
B L
U
G N T N
E
I
T T O
N C A D M
A
I
I
L O
M
I
I
U M N
I
D N
J
E N
Z E
L
I
N E H L
H
G H P
B R O M
I
N E D A
P
L
N E H T U R C S
P
K L M U
Y O
P M Q R T S C M U V H E O H
I
Y D U
R X E U A S
C R N U R B D D
P E N
I
E
J
I
T
I
L
B L
F G O H O
I
H
U
P
R
H
O R L
E M
O E N O D V P R D N
L Q T
K N D G A R T
N R
T H H
A A H
C N E D S T
U H Y A H E M P E R B E N
I
N
I
O B
I
I
U M O C
N E E
I
I
R U N T
I
D E
T
T
A T S A
A N A B E
L
E G O S C
I
S M U
I
N
I
T C A L
C
I
U M M U
I
I
I
N
I
A
I
S
I
I
A
O G N L
F
F E A M L M T
S
L N D L
N O C R
I
Z
U U D N
I
A
E
N
T T
L
I
I
A G H H
L
U
L
T P A S
I
M
V E R U E
E
O T U U H
I
E N
U
L
U N G C M N N R M Y M M R O R N T A H T U M S
I
B
O R M M M O U
G M
L E
I
L D E U L M B O R O N M L E N N T S S
M N O B R A C M
E S U L
U
L H
L
N U H T
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
L U O R
W S A Y X M D B Z
K
S
F
D E
N O E O B O C
E
R G
I
I
T U E
I
D B
U P U T U N E T
E
I
A H E L R N
P
L
T
I
P E
I
U G M
I
L
I
R T T
Y N T
I
I
M N M
I
U U L M N
R
I
U M V
Y
I
F
I
A
I
U E M E C H R O M
I
U M A N
L
T S U O X Y G E N M
E E A V U E R M U
S E C M N B M K
T
I
I
R
C E M N M D E S E N A G N A M A M P
S
I
T R O N
D
T
I
V
U M R A
E
N
N E A D A N B E
I
U A R
L A
O H T M A U D R M E
F D
C M U A M U
I
M S O L D
Directions: Complete the following paragraphs about the periodic table by filling each blank with the correct term.
In the modern periodic table, elements are listed by increasing 1. ________________. Each box
represents an 2. ________________. A box contains the name, atomic number,
3. ________________, and 4. ________________ for the element.
Vertical columns in the table are called 5. ________________. Most elements in a column have
the same number of 6. ________________ in the outer energy level and tend to have similar
7._________________.
Horizontal rows in the table are called 8. ________________. The elements on the left side of the
table are 9. ________________. Groups 3–12 contain metals known as 10. ________________.
Elements on the right side are 11. ________________.
Properties of Atoms and the Periodic Table
29
Meeting Individual Needs
O O S
I
Name
1
Date
Enrichment
Class
The Building Blocks of Matter
From experiments involving the high-speed collision of particles, scientists have determined that
heavy nuclear particles, such as protons and neutrons, are composed of quarks. The name “quark”
was taken from a novel. Quarks are classified into six flavors—up, down, strange, charm, bottom,
and top. The flavors are not related to any physical characteristics of the quarks themselves, but are
used as classifications. Unlike protons and electrons, which carry whole charges of +1 or –1, quarks
carry fractional charges. The following table lists some information about quarks.
Quarks
Symbol
Charge
Name
Symbol
Charge
up
u
2/3
down
d
1/3
strange
s
1/3
charm
c
2/3
bottom
b
1/3
top
t
2/3
Mass
1. Use the library to find the name of the author and novel from which the word “quark” was
taken.
2. Use the library to draw a time line showing the history of quarks.
3. Protons and neutrons are composed of triplets of up and down quarks. Use the information in the
table to determine which of the following quark triplets represents a proton and which represents
a neutron.
udd __________________
uud __________________
4. A heavier nuclear particle is composed of a triplet of strange quarks. What is the charge of this
particle?
30 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
Name
Name
Enrichment
Class
The Mole
You have learned that the mass of atoms is measured in atomic mass units.
This unit is too small to use in everyday measurement. It would be simpler to
have a number of atoms that would have a mass in grams that is equal to the
mass of one atom in atomic mass units. The same number would fit all elements,
because equal numbers of different atoms always have the same mass ratio.
Chemists have found that 6.02 ✕ 1023 atoms of an element have a mass in
grams equivalent to the mass of one atom in atomic mass units. This counting
unit is called a mole. For example, one mole of helium atoms has a mass of 4
grams because helium has a mass number of 4.
Do you know how big a number a mole is? Suppose the entire population of
the world, more than four billion people, were assigned to count the number of
atoms in one mole of helium. If each person counted one atom per second and
worked a 48-hour work week, the task would take more than 10 million years. If
you had one mole of pennies, you would have enough money to pay all the
expenses of the United States for the next billion years.
1. A mole is a certain number of items. What number does each of the following terms represent?
a. dozen ______________
d. mole ______________
b. billion ______________
e. gross ______________
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
c. million ______________
2. Using a laboratory balance, measure and record the mass of one mole of each of the following
elements: carbon, iron nails, zinc metal, and copper wire.
3. Find the mass, in grams, of each of the following:
a. 2 moles of aluminum ______________
b. 4 moles of magnesium ______________
c. 3 moles of helium ______________
4. How many moles are in each of the following:
a. 156 grams of chromium ______________
b. 156 grams of potassium ______________
c. 119 grams of uranium ______________
5. Why is the counting unit called a mole useful for chemists?
Properties of Atoms and the Periodic Table
31
Meeting Individual Needs
2
Date
Name
3
Date
Enrichment
Class
Predicting an Element’s
Group and Period
Several scientists, including Newlands, Meyer, and Mendeleev worked on classification systems
that grouped elements according to their properties. They found that these properties repeated in a
regular or periodic manner. This fact was used to predict properties of undiscovered elements.
Review electron arrangement from your textbook. In Table 1, write the maximum number of
electrons that can fill each energy level on the blanks in the table heading. Write the total number
of electrons for each element in the first column labeled Total. For each element, assign the correct
number of electrons to each energy level. Complete Table 2 by using the information from the six
elements studied.
Electrons
Element
Total
Level 1
Level 2
Level 3
Number of
outer electrons
Located in
group
1. Argon
2. Carbon
3. Helium
4. Lithium
5. Silicon
6. Sodium
Table 2
Element
Energy level of
outer electrons
Located in
period
7. Ar
8. C
9. He
10. Li
11. Si
12. Na
13. How is the element’s period related to the number of energy levels over which its electrons are
spread?
14. How can you predict an element’s group and period?
32 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
Table 1
Name
Date
Note-taking
Worksheet
Section 1
Class
Properties of Atoms and the
Periodic Table
Structure of the Atom
A. ____________ are abbreviated in scientific shorthand—first letter or two of element’s name
B. ________—smallest piece of matter that still has the properties of the element
1. ___________ have electrical charge of 1+.
3. _____________ have electrical charge of 1-.
4. Protons and neutrons are in the ___________ of an atom; electrons surround the nucleus.
C. Protons and neutrons are made up of smaller particles called __________.
1. Six quarks are known to exist; the sixth is called the _______ quark.
D. Scientists use scaled-up __________ to represent atoms.
1. Early models of atoms used a solid __________.
2. Current __________________ model shows electrons traveling in specific energy levels
around a nucleus of protons and neutrons.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Section 2
Masses of Atoms
A. _______________—composed mostly of the protons and neutrons in the nucleus
1. Unit of measurement for atomic particles is ____________________ (amu) which is
one-twelfth the mass of a carbon atom containing six protons and six neutrons.
2. _________________—the number of protons in an atom; number of protons also
identifies the element
3. The sum of the number of protons and neutrons in the nucleus of an atom is
the _______________.
B. ____________—atoms of the same element with different numbers of neutrons
1. Different isotopes have different ______________.
2. Number of ____________ is equal to mass number minus atomic number.
3. Name of ___________ followed by mass number identifies the isotope.
4. _______________________ is the weighted-average mass of an element’s isotopes.
5. Average atomic mass is closest to its most ____________ isotope.
Properties of Atoms and the Periodic Table
33
Meeting Individual Needs
2. ____________ do not have an electrical charge.
Name
Date
Class
Note-taking Worksheet (continued)
Section 3
The Periodic Table
A. Elements are organized in the __________________ by increasing atomic number.
1. In the late 1800’s, Dmitri Medeleev devised the first periodic table based on
_______________.
2. In 1913, Henry G. J. Moseley arranged the elements by _________________ rather than
atomic mass.
B. Vertical columns in the periodic table are __________ of elements with similar properties.
2. Each of the seven energy levels can have a ___________ number of electrons.
a. Energy level one can contain at most _______ electrons.
b. Energy level two can contain at most _________ electrons.
3. Each row in the periodic table ends when an outer energy level is __________.
4. _________________________ use the element symbol and dots to represent outer energy
level electrons.
C. ___________—horizontal rows of elements that contain increasing numbers of protons and
electrons.
1. Elements are ______________ as metals, nonmetals, or metalloids (semimetals).
2. Elements are _______________ in laboratories all over the world.
D. The ________ elements exist all over the universe.
1. Hydrogen and helium are the ___________________ of other naturally occurring elements.
2. ______________ spread heavier elements throughout the universe.
34 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Meeting Individual Needs
1. Elements in the same group have the same number of _____________ in their outer energy
level.
Name
Date
Class
Properties of Atoms and
the Periodic Table
Chapter
Review
Part A. Vocabulary Review
Directions: On the space at the left, write the term that correctly completes each statement. Use each term once.
metals
groups
electrons
chemical symbol
isotopes
metalloids
nucleus
average atomic mass
electron cloud
transition elements
atomic number
mass number
periods
quarks
periodic table
1. A capital letter or a combination of a capital letter and a small letter
that is used to represent an element is called a(n) ______.
2. The horizontal rows of elements are called ______.
3. An average of the masses of all the isotopes that occur in nature for
an element is the ______.
4. Vertical columns of elements are called ______.
5. Elements in the middle of the periodic table, groups 4 through 7, are
called the ______.
7. Protons and neutrons can be subdivided into ______ by colliding
them.
8. The center of an atom where protons and neutrons are located is
the ______.
9. A total count of the neutrons and protons in an atom is the ______.
10. Atoms of the same element but with different numbers of neutrons
are ______.
11. Elements that are found on the left side of the periodic table are ______.
12. Elements that have some properties of both metals and nonmetals
are ______.
13. The particles that move about the nucleus and have a negative
charge are ______.
14. The region around the nucleus occupied by electrons is a(n) ______.
15. A chart that shows the classification of elements is called the ______.
Properties of Atoms and the Periodic Table
37
Assessment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. The number of protons in an atom is the ______.
Name
Date
Class
Chapter Review (continued)
Part B. Concept Review
Directions: Complete the table below by writing the correct information in the blank spaces.
Chemical
symbol
Element
Atomic
number
Number of
protons
Number of
neutrons
Mass
number
11
11
12
23
6
6
12
26
30
56
16
32
1. Sodium
2. Carbon
C
3.
Fe
26
4. Sulfur
S
16
5. Nitrogen
N
7
7
6. Oxygen
O
8
8
8
7.
He
2
2
2
8. Chlorine-35
Cl
17
17
9. Copper
Cu
29
29
35
17
20
Cl
10. Chlorine-37
14
4
35
37
1
18
11
Assessment
Na
2
13
14
15
16
17
23
26
3
A
4
5
6
7
8
9
10
11
12
C
Fe
Fe
55.8
79
Au
197
Au
B
11. Which element has a greater atomic mass, A or B?
12. Which element is a metal, B or C?
13. In which group is gold?
14. What is the average atomic mass of iron?
15. What is the atomic number of sodium?
38 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Directions: Refer to the periodic table below and the boxes at the right of the table to answer questions 11–15.
Name
1
Date
Section Focus
Transparency Activity
Class
Subatomic Collision
Transparency Activities
1. Why do you think scientists have only recently discovered these
subatomic particles?
2. What might scientists learn by breaking apart atomic nuclei?
44 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
An individual atom is so small that it would take 50 million of
them lined up in a row to equal one centimeter! Atoms, however, can
be divided into component parts, and, amazingly, some of these parts
have particles that are tinier yet. Below is an image created by these
subatomic particles taken in a device called a bubble chamber.
Name
2
Date
Section Focus
Transparency Activity
Class
Carbon Cat
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
How old are these mummified cats found in an Egyptian tomb?
Carbon-14 holds the answer. Carbon-14 is a radioactive form of
carbon, an element found in every living thing. By measuring how
much carbon-14 remains in these cats, scientists can tell approximately how many years ago the cats were buried.
1. Carbon-14 decays over time. What does “decay” mean?
2. Why do you think carbon is used by scientists to date objects such
as mummies, bones, and cloth wrappings?
3. Is it possible to use carbon-14 dating on things that were never
alive? Why or why not?
Properties of Atoms and the Periodic Table
45
Name
3
Date
Section Focus
Transparency Activity
Class
What makes the
glass glow?
1. Of what materials is glass usually made?
Transparency Activities
2. Why do you think the glass glows?
3. Why might prolonged work with such glass be dangerous?
46 Properties of Atoms and the Periodic Table
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
When you hear the word uranium, you might think of nuclear
power. Uranium, though, was used in the 19th century by European
glassmakers to create what was called uranium glass. This interesting
glass had a yellowish-green color and glows under certain lighting
conditions.
Name
Date
1
Teaching Transparency
Activity
Class
Electron Cloud Model
Nucleus
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Electron
cloud
Properties of Atoms and the Periodic Table
47
Name
Teaching Transparency Activity
Date
Class
(continued)
1. What is the region around the nucleus called?
2. What was the name of the Greek who proposed the idea that atoms made up all substances?
3. What is an electron cloud?
4. What determines how far each electron travels from the nucleus?
5. Why can’t electron positions be pinpointed?
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
6. Electrons are located in a cloud surrounding what part of the atom?
48 Properties of Atoms and the Periodic Table
Name
Date
Assessment
Transparency Activity
Class
Properties of Atoms
and the Periodic Table
Directions: Carefully review the table and answer the following questions.
Characteristics of Some Alkaline Earth Metals
Atomic
number
Mass
number
Melting
point (˚C)
Boiling
point (˚C)
Magnesium
12
24
651
1105
Calcium
20
40
842
1494
Strontium
38
88
769
1384
Barium
56
137
725
1640
1. According to the table, which alkaline Earth metal has a mass
number greater than 100?
A Magnesium
C Strontium
B Calcium
D Barium
2. According to the table, which element has the LOWEST atomic
number?
F Magnesium
H Strontium
G Calcium
J Barium
3. According to the table, which element has the HIGHEST melting
point?
A Magnesium
C Strontium
B Calcium
D Barium
Transparency Activities
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.
Element
4. The number of neutrons in the nucleus of an atom is equal to
the mass number minus the atomic number. According to this
definition and the table, how many neutrons are in the nucleus
of a strontium atom?
F 20
G 38
H 50
J 81
Properties of Atoms and the Periodic Table
49