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Chapter 6
THE PERIODIC TABLE
1
Introduction
Activity
2
Label the GROUPS & PERIODS
(on BOTH sides)
1
1
18
2
13
14
15
16
17
2
3
3
4
5
6
7
8
9
10
11
12
4
5
6
7
6
7
Make Yourself a KEY!
3
4
Metals
5
Transition Metals
6
Metalloids
7
Non Metals
Make Yourself a KEY!
8
9
Representative Elements
1
1
18
2
13
14
15
16
17
2
3
3
4
5
6
7
8
9
10
11
12
4
5
6
7
6
7
Make Yourself a KEY!
10
Hydrogen
11
Alkali Metals
12
Alkaline-Earth Metals
13
Boron Group
14
Carbon Group
15
Nitrogen Group
16
Oxygen Group
17
Halogens
18
Noble Gases
19
Lanthanides
20
Actinides
21
All Together!
Make Yourself a KEY!
22
Chapter 6 Vocabulary
1.Alkali metals
10. Ionization energy
2.Alkaline earth metals
11. Metalloids
3.Anion
12. Metals
4.Atomic radius
13. Noble gases
5.Cation
14. Nonmetals
6.Electronegativity
15. Periodic law
7.Halogens
16. Representative elements
8.Inner transition metal
17. Transition metal
9.Ion
23
24
Review from yesterday! Complete the chart:
Element
Symbol
Group
Number
Period
Number
Group Name
Metal, Nonmetal,
or Metalloid?
Nitrogen
N
15
2
Nitrogen Group
Nonmetal
Platinum
Pt
10
6
Transition
Metals
Metal
Tin
Sn
14
5
Carbon
Group
Metal
Antimony
Sb
15
5
Nitrogen
Group
Metalloid
Potassium
K
1
4
Alkali
Metals
Metal
Bromine
Br
17
4
Halogens
Nonmetal
25
Section 6.1 Notes
Organizing the Elements
READ PAGES 155-160
26
How did chemists begin to organize
the known elements?
Chemists used the properties of
elements to sort them into GROUPS
27
.
1700
13 elements were identified
Included:
- Copper
- Silver
- Gold
- Carbon
28
1765-1775
5 new elements were identified
Included:
- Hydrogen
- Nitrogen
- Oxygen
29
1829
J.W. Döbereiner (Johann Wolfgang)
◦ German chemist
◦ Grouped some elements into triads
◦ Set of three elements with similar properties
30
Cl, Br, I have very similar chemical properties.
Can you find them on the Periodic Table?
31
1869
Dmitri Mendeleev
◦Russian chemist
◦Published the first table of
elements
◦Arranged the elements in order of
increasing atomic mass
32
Mendeleev was amazing because he
• left spaces in his table for elements not
yet discovered
• predicted properties for these
undiscovered elements correctly
33
Mendeleev’s
st
1
Periodic Table
In this early version of
Mendeleev’s periodic
table, the rows contain
elements with similar
properties.
34
What was wrong with
Mendeleev’s Periodic Table?
Let’s look at your Periodic Table
What did Mendeleev’s Periodic Table go by?
◦ Atomic Mass
Any discrepancies?
What does yours go by?
◦ Atomic Number
35
1913
Henry Moseley
◦British physicist
◦Determined the atomic number for
elements
◦Arranged the elements in order of
increasing atomic number
◦ Today’s Periodic Table
36
Today’s Periodic Table
37
Periodic Law
when elements are arranged by
increasing atomic number,
properties of the elements tend
to repeat
38
Metals
• to the left of the stair-step line
• most of the elements (80%)
• Properties
◦ Good conductors of heat and electricity
◦ Shiny (luster)
◦ Solid at room temperature
◦ Except liquid mercury
◦ Ductile
◦ Drawn into wires like copper wire
◦ Malleable
◦ Hammer into thin sheets like aluminum foil
39
Metals
40
Of all the elements that make up the
world in which we live – solids, liquids,
gases – most are metals.
• There are metals such as
aluminum, zinc, gold,
copper, tin, and nickel –
and ones you might not
think of as metals, such
as calcium, which is
present in bones and
teeth. Did you know that
the average human body
contains more than 2 lbs
of calcium?
Ni
Ca
Zn
Sn
AlAu
Cu
41
Some metals are dangerous.
• Potassium reacts
violently with water
creating hydrogen
gas. Cesium and
rubidium will
explode if they
touch water.
K
Cs
https://www.youtube.com/watch?v=uixxJtJPVXk
Rb
42
Mercury is poisonous.
• In fact, the phrase
“mad as a hatter”
arose because in
past centuries,
fumes from the
mercury used in
the hat making
process affected
the mental health
of workers in that
industry!
43
• The high density of
• Platinum, Pt, is one of
osmium, Os, – a metal
the rarest and most
in the same period as
valuable of all metals. It
platinum – means that
is used to make jewelry
a brick of the metal can
and used extensively in
weigh as much as a
industry.
small car. Osmium is
used in fountain pen
nibs and surgical
needles.
44
Can you find element names hidden in these sentences?
1.
2.
3.
4.
5.
Nick, elbows off the table please!
Grandpa is looking older.
Your feet are a little stinky.
Do you care about the environment?
I placed a simple ad in the paper.
45
Nonmetals
to the right of the stair-step line
most are gases, few solids
◦except liquid bromine
Properties:
◦poor conductors of heat and electricity
◦solids tend to be brittle
46
Nonmetals
47
Diatomic Elements
BrINCl HOF
LABEL THEM ON YOUR P.T.
48
Metalloids
Touch the stair-step line
◦ Except aluminum and polonium
Have properties of both metals and
nonmetals
Si
49
Metalloids
50
Metals / Metalloids / Nonmetals
Just like Intro Activity
51
Metals, Nonmetals, and Metalloids
Inferring:
What is the purpose for the black stair-step line?
52
Quick Quiz
SECTION 6.1
53
1. The modern periodic table has
elements arranged in order of
a. colors.
b. melting and boiling points.
c. increasing atomic mass.
d. increasing atomic number.
54
2. Mendeleev arranged the
elements in his periodic table in
order of increasing
a. atomic mass.
b. number of protons.
c. number of electrons.
d. atomic number.
55
3. Which one of the following is NOT
a general property of metals?
a. ductility
b. malleability
c. having a high luster
d. poor conductor of heat and
electricity
56
What’s Next?
Book Work:
◦Page 160 #’s 1-7
57
Page 160 #1-7
1.
2.
3.
4.
5.
How did chemists begin the process of organizing elements?
What property did Mendeleev use to organize his periodic
table?
How are elements arranged in the modern periodic table?
Name the three broad classes of elements.
Which of the sets of elements have similar physical and
chemical properties?
a.
b.
c.
6.
Identify each element as a metal, metalloid, or non-metal.
a.
b.
c.
d.
7.
Oxygen, nitrogen, carbon, boron
Strontium, magnesium, calcium, beryllium
Nitrogen, neon, nickel, niobium
Gold
Silicon
Sulfur
Barium
Name two elements that have properties similar to those of
the element sodium.
58
1. How did chemists begin the
process of organizing elements?
Chemists used the properties of
elements to sort them into
groups, or triads.
2. What property did Mendeleev use
to organize his periodic table?
Increasing atomic mass
3. How are elements arranged in the
modern periodic table?
Increasing atomic number
4. Name the three broad classes of
elements.
Metals, Non-Metals, and
Metalloids
5. Which of the sets of elements have
similar physical and chemical
properties?
(B)
strontium, magnesium,
calcium, beryllium
6. Identify each element as a metal,
metalloid, or non-metal.
A) Metal (Au)
B) Metalloid (Si)
C) Non Metal (S)
D) Metal (Ba)
7. Name two elements that have
properties similar to those of the
element sodium.
Li, K, Rb, Cs, Fr
Section 6.2 Notes
Classifying the Elements
READ PAGES 161-167
66
Representative Elements
Groups 1A through 8A
◦Groups 1, 2, 13-18
67
Representative Elements
68
69
Transition Elements
Transition metals
◦Group B
◦ Groups 3-12
Inner transition metals
◦Last 2 rows on the periodic table
70
Transition Elements
Inner Transition Elements
71
Similar to your colored Periodic Table
72
Periodic Table Key
The periodic table displays the symbols and
names of the elements, along with
information about the structure of their
atoms.
73
Quick Quiz
SECTION 6.2
74
1. Which one of the following is incorrectly
labeled?
a. Ne, noble gas
b. Cu, transition metal
c. Ga, transition metal
d. Cl, halogen
75
What’s Next?
Book Work:
◦Page 167 #’s 10, 12, 14
76
10. What information can be included in a
periodic table?
Symbols and names.
Structure.
Properties.
12. Why do the elements potassium and sodium
have similar chemical properties?
K and Na are in the same
group.
(Alkali Metals)
14. Which of the following elements are
transition metals?
Cu, Sr, Cd, Au, Al, Ge, Co
Section 6.3 Notes
Periodic Trends
READ PAGES 170-178
80
What does the word periodic
mean to you?
Periodic
◦Happens in intervals
What are some examples of things that
happen periodically?
◦Birthdays, holidays, periodicals
81
Why is the periodic table called “The
Periodic Table”?
the properties of elements repeat
82
Trend
◦A predictable
change
Periodic Trend
◦ Properties of the elements
repeat and form patterns
◦ Allows us to make
predictions about the
chemical behavior of
elements
◦ How elements will react with other
elements
◦ Many trends exist in the
periodic table
83
Atomic Radius
Half the distance between two nuclei of the
same atom
Describes the size of the atom
84
Atomic Radius
Trend
DOWN A GROUP
Increases
Why?
◦ Number of energy
levels increases
◦ Period 1 = 1 e. l.,
◦ Period 2 = 2 e. l.,
◦ Etc…
H
Li
Na
K
Rb
85 85
Atomic Radius Trend
Na Mg
Al Si
P
S Cl
Ar
ACROSS A PERIOD
Decreases
Why?
◦ Electron / proton attraction increases
◦ Opposite of tug of war!
86
Trends in Atomic Size
Predicting:
If a halogen and an alkali metal are in the same
period, which one will have the larger radius?
alkali metal
87
Shielding Effect
“shielding” is the nuclear
pull on electrons
Valence electrons are
“shielded” from the pull /
charge of the nucleus by all
the electrons in between.
88
Ions
An atom with a charge
Cation
◦ Positively charged ion
◦ Formed by metals
◦ Lost electrons
Anion
◦ Negatively charged ion
◦ Formed by nonmetals
◦ Gained electrons
89
How do ions form?
Positive and negative ions form when
electrons are transferred between
atoms.
90
Positive Ions
When a sodium atom loses an electron, it becomes a positively charged ion.
Interpreting Diagrams:
What happens to the protons and neutrons during these changes?
91
Negative Ions
When a chlorine atom gains an electron, it becomes a negatively charged ion.
Interpreting Diagrams:
What happens to the protons and neutrons during these changes?
92
Cation
Metals
Anion
Nonmetals
93
This diagram compares the relative sizes of atoms and ions for selected
alkali metals and halogens. The data are given in picometers.
Comparing and Contrasting:
◦ What happens to the radius when an atom forms a cation?
◦ When an atom forms an anion?
94
Ionic Size
Size of the ion compared to the parent atom
Cations
◦ Positive ions are smaller than the atom it comes from
◦ Why?
◦ It lost electrons
Anions
◦ Negative ions are larger than the atom it comes from
◦ Why?
◦ It gained electrons
95
Ionic Radius Increases
Trends in Ionic Size
Ionic Radius Decreases
96
First Ionization Energy
energy needed to remove an
electron from an atom
97
First Ionization Energy Trend
DOWN A GROUP
Decreases
Why?
◦ Valence electrons are
farther away from the
nucleus
ACROSS A PERIOD
Increases
Why?
◦ The atom becomes more
stable with more valence
electrons
98
Multiple
Ionization
Energies
What would the 2nd
Ionization Energy mean?
Energy needed
to remove the
second electron
What would the 3rd
Ionization Energy mean?
Energy needed
to remove the
third electron
Why are elements such as H and He missing
some ionization energy values?
99
Trends in Ionization Energy
Predicting:
Which element would have the larger first
ionization energy, an alkali metal in period 2 or an
alkali metal in period 4?
Period 2 alkali metal
100
Electronegativity
The ability of an atom to attract
electrons to itself when bonded
to another atom
101
Electronegativity Trend
DOWN A GROUP
ACROSS A PERIOD
Decreases
Increases
Why?
Why?
◦ Valence electrons are
farther away from the
nucleus
◦ Same reason as
ionization energy
◦ Atom becomes more
stable with more valence
electrons
◦ Same reason as
ionization energy
◦ Don’t count noble gases
102
103
Most Active Elements
Most active metal
◦ Fr (Francium)
Why?
◦ Lowest
electronegativity
Most active nonmetal
◦ F (Fluorine)
Why?
◦ Highest electronegativity
104
Summary of
Trends
RECAP
105
Decreases
Increases
Atomic Size
106
Increases
Decreases
Ionization energy
107
Increases
Decreases
Electronegativity
108
Page 178: Draw arrows to show periodic
trends below.
109
Quick Quiz
SECTION 6.3
110
1. Which of the following sequences is correct
for atomic size?
a. Mg > Al > S
b. Li > Na > K
c. F > N > B
d. F > Cl > Br
111
2. Metals tend to
a. gain electrons to form cations.
b. gain electrons to form anions.
c. lose electrons to form anions.
d. lose electrons to form cations.
112
3. Which of the following is the most
electronegative element?
a. Cl
b. Se
c. Na
d. I
113
What’s Next?
Book Work:
◦Page 178 #’s 16-23
114
16. How does atomic size change within groups and across
periods?
In general, atomic size
increases from top to
bottom within a group and
decreases from left to right
across a period.
17. When do ions form?
Positive and negative ions
form when electrons are
transferred between atoms.
18. What happens to first ionization energy within groups and
across periods?
First ionization energy tends
to decrease from top to
bottom within a group and
increase from left to right
across a period.
19. Compare the size of ions to the size of atoms from which
they form.
Cations (+) are always smaller
than the atoms from which they
form.
Anions (-) are always larger than
the atoms from which they
form.
20. How does electronegativity vary within groups and across
periods?
In general, electronegativity
values decrease from top to
bottom within a group. For
representative elements, the
values tend to increase from
left to right across a period.
21. In general, how can the periodic trends displayed by the
elements be explained?
The trends that exist among
these properties can be
explained by variations in
atomic structure.
22. Arrange the elements in order of decreasing atomic size:
Sulfur, Chlorine, Aluminum, Sodium.
Sodium > Aluminum > Sulfur > Chlorine
23. Which element in each pair has the larger first ionization
energy?
a) Sodium, Potassium
b) Magnesium, Phosphorus
You need to know the
NAME (Spelling Counts) and SYMBOL of
the following elements (not the location)
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
K
Ca
Ti
Cr
Mn
Fe
Co
Ni
Rb
Cu
Zn
Ag
Ba
Pt
Au
As
Br
Sn
Hg
I
Pb
Fr
123
The Periodic Law
A PUZZLE ACTIVITY
124
Introduction
The present organization of the elements is a product of the first periodic table published by
Dmitri Mendeleev in 1869. The amazing accuracy of his predictions has been very
important to chemists in this century. However, the basis of his arrangement was the
atomic masses of the elements. This approach proved incorrect as it would have placed
some elements in a group with dissimilar properties. Henry Moseley rearranged the table
on the basis of the atomic numbers of the elements. In accordance with Moseley’s revision,
the periodic law states: the properties of the elements are periodic functions of their atomic
numbers.
Each of the 100+ known elements has its own set of characteristic properties. These range
from solid to gas, lustrous to dull, low to high melting points, various colors, and so on. The
elements are arranged within the periodic table into groups (vertical columns) and periods
(horizontal rows). This arrangement reflects the periodic or repeating nature of the
properties of the elements.
125
Purpose
In this activity, you will use your
knowledge of periodic properties and a
list of clues to correctly arrange the
elements from a scrambled periodic
table.
126
Procedure / Clues
The following sets of elements belong together in groups:
◦ PSIF, JXBE, ZRD, LHT, QKA, WOV, GUN, YMC
Letter clues:
J has an atomic number three times that of T
U has a total of six electrons
I2A is the simple formula of an oxide
P is less dense than S
S is an alkali metal
E is a noble gas
W is a liquid
Z has the smallest atomic mass in its group
B has ten protons
O has an atomic number larger than V
D has the largest atomic mass of its group
C has five electrons its outer energy level
F is a gas
X has an atomic number one higher than F
L is an alkaline earth element with atomic mass of 40
Y is a metalloid
O is a halogen
The atomic mass of T is more than that of H
Q has an atomic mass 2 times A
Atoms of I are larger than those of S
M has an atomic number one less than that of A
The atomic radius of K is the largest of the group
The electrons of atom N are distributed over three energy levels.
127
Place the correct letter below in their
appropriate spot according to the Periodic
Table!
1
2
13
14
15
16
17
18
Then you know
that GUN are in
this group
Let’s do one together…
J has an atomic number three times that of T
U has a total of six electrons
128
Have Fun
EXTRA CREDIT – DUE TOMORROW
129
Answers
1
2
13
14
15
16
17
F
18
X
P
H
Z
U
M
A
V
B
S
T
R
N
C
Q
O
E
I
L
D
G
Y
K
W
J
130