Chemistry: Matter and Change

1
(No Transcript)
2
Chapter Menu
The Periodic Table and Periodic Law
Section 6.1 Development of the Modern Periodic
Table Section 6.2 Classification of the
Elements Section 6.3 Periodic Trends
Click a hyperlink or folder tab to view the
corresponding slides.
Exit
3
Section 6-1
Section 6.1 Development of the Modern Periodic
Table

• Trace the development of the periodic table.

• Identify key features of the periodic table.

atomic number the number of protons in an atom
The periodic table evolved over time as
scientists discovered more useful ways to compare
and organize the elements.
4
Section 6-1
Section 6.1 Development of the Modern Periodic
Table (cont.)
group period representative elements transition
elements metal alkali metals alkaline earth metals
transition metal inner transition
metal lanthanide series actinide
series nonmetals halogen noble gas metalloid
5
Section 6-1
Development of the Periodic Table

• In the 1700s, Lavoisier compiled a list of all
  the known elements of the time.

6
Section 6-1

• Newlands noticed when the elements were arranged
  by increasing atomic mass, their properties
  repeated every eighth element.

7
Section 6-1
Development of the Periodic Table (cont.)

• Mendeleev demonstrated a connection between
  atomic mass and elemental properties.

• Moseley rearranged the table by increasing atomic
  number, and resulted in a clear periodic pattern.

8
Section 6-1
The Modern Periodic Table

• The modern periodic table contains boxes which
  contain the element's name, symbol, atomic
  number, and atomic mass.

9
Section 6-1
The Modern Periodic Table (cont.)

• Columns of elements are called groups.

• Rows of elements are called periods.
• Elements in groups 1,2, and 13-18 possess a wide
  variety of chemical and physical properties and
  are called the representative elements.
• Elements in groups 3-12 are known as the
  transition metals.

10
Section 6-1
The Modern Periodic Table (cont.)

• Elements are classified as metals, non-metals,
  and metalloids.

• Metals are elements that are generally shiny when
  smooth and clean, solid at room temperature, and
  good conductors of heat and electricity.
• Alkali metals are all the elements in group 1
  except hydrogen, and are very reactive.
• Alkaline earth metals are in group 2, and are
  also highly reactive.

11
Section 6-1
The Modern Periodic Table (cont.)

• The transition elements are divided into
  transition metals and inner transition metals.

• The two sets of inner transition metals are
  called the lanthanide series and actinide series
  and are located at the bottom of the periodic
  table.

12
Section 6-1
The Modern Periodic Table (cont.)

• Non-metals are elements that are generally gases
  or brittle, dull-looking solids, and poor
  conductors of heat and electricity.

• Group 17 is composed of highly reactive elements
  called halogens.
• Group 18 gases are extremely unreactive and
  commonly called noble gases.

13
Section 6-1
The Modern Periodic Table (cont.)

• Metalloids have physical and chemical properties
  of both metals and non-metals, such as silicon
  and germanium.

14
Section 6-1
The Modern Periodic Table (cont.)
15
Section 6-1
Section 6.1 Assessment
What is a row of elements on the periodic table
called? A. octave B. period C. group
D. transition

1. A
2. B
3. C
4. D

16
Section 6-1
Section 6.1 Assessment
What is silicon an example of? A. metal
B. non-metal C. inner transition metal
D. metalloid

1. A
2. B
3. C
4. D

17
End of Section 6-1
18
Section 6-2
Section 6.2 Classification of the Elements

• Explain why elements in the same group have
  similar properties.

valence electron electron in an atom's outermost
orbitals determines the chemical properties of
an atom

• Identify the four blocks of the periodic table
  based on their electron configuration.

Elements are organized into different blocks in
the periodic table according to their electron
configurations.
19
Section 6-2
Organizing the Elements by Electron Configuration

• Electrons in the highest principal energy level
  are called valence electrons.

• All group 1 elements have one valence electron.

20
Section 6-2
Organizing the Elements by Electron Configuration
(cont.)

• The number of valence electrons for elements in
  groups 13-18 is ten less than their group number.

• The energy level of an elements valence
  electrons indicates the period on the periodic
  table in which it is found.

21
Section 6-2
Organizing the Elements by Electron Configuration
(cont.)
22
Section 6-2
The s-, p-, d-, and f-Block Elements

• The shape of the periodic table becomes clear if
  it is divided into blocks representing the atoms
  energy sublevel being filled with valence
  electrons.

23
Section 6-2
The s-, p-, d-, and f-Block Elements (cont.)

• s-block elements consist of group 1 and 2, and
  the element helium.

• Group 1 elements have a partially filled s
  orbital with one electron.
• Group 2 elements have a completely filled s
  orbital with two electrons.

24
Section 6-2
The s-, p-, d-, and f-Block Elements (cont.)

• After the s-orbital is filled, valence electrons
  occupy the p-orbital.

• Groups 13-18 contain elements with completely or
  partially filled p orbitals.

25
Section 6-2
The s-, p-, d-, and f-Block Elements (cont.)

• The d-block contains the transition metals and is
  the largest block.

• There are exceptions, but d-block elements
  usually have filled outermost s orbital, and
  filled or partially filled d orbital.
• The five d orbitals can hold 10 electrons, so the
  d-block spans ten groups on the periodic table.

26
Section 6-2
Section 6.2 Assessment
Which of the following is NOT one of the
elemental blocks of the periodic table?
A. s-block B. d-block C. g-block D. f-block

1. A
2. B
3. C
4. D

27
Section 6-2
Section 6.2 Assessment
Which block spans 14 elemental groups?
A. s-block B. p-block C. f-block D. g-block

1. A
2. B
3. C
4. D

28
End of Section 6-2
29
Section 6-3
Section 6.3 Periodic Trends

• Compare period and group trends of several
  properties.

principal energy level the major energy level of
an atom

• Relate period and group trends in atomic radii to
  electron configuration.

ion ionization energy octet rule electronegativity
Trends among elements in the periodic table
include their size and their ability to lose or
attract electrons
30
Section 6-3
Atomic Radius

• For elements that occur as molecules, the atomic
  radius is half the distance between nuclei of
  identical atoms.

31
(No Transcript)
32
Section 6-3
Atomic Radius

• Atomic size is a periodic trend influenced by
  electron configuration.

• There is a general decrease in atomic radius from
  left to right, caused by increasing positive
  charge in the nucleus.

33
Section 6-3
Atomic Radius (cont.)
34
(No Transcript)
35
Section 6-3
Atomic Radius (cont.)

• Atomic radius generally increases as you move
  down a group.

36
Section 6-3
Ions

• An ion is an atom or bonded group of atoms with a
  positive or negative charge.

• When atoms lose electrons and form positively
  charged ions, they always become smaller because

The loss of a valence electron can leave an empty
outer orbital resulting in a small radius.
37
Section 6-3
Ionization Energy

• Ionization energy is defined as the energy
  required to remove an electron

• The energy required to remove the first electron
  is called the first ionization energy.

38
Section 6-3
Ionization Energy (cont.)
39
Section 6-3
Ionization Energy (cont.)

• First ionization energy increases from left to
  right across a period.
• First ionization energy decreases down a group
  because atomic size increases and less energy is
  required to remove an electron farther from the
  nucleus.

40
Section 6-3
Ionization Energy (cont.)
41
Section 6-3
Octet rule and formation of Ions

• The octet rule states that atoms tend to gain,
  lose or share electrons in order to acquire a
  full set of eight valence electrons.

• The octet rule is useful for predicting what
  types of ions an element is likely to form.

42
Section 6-3
Ionization Energy (cont.)

• The electronegativity of an element indicates its
  relative ability to attract electrons in a
  chemical bond.

• Electronegativity decreases down a group and
  increases left to right across a period.

43
Section 6-3
44
Section 6-3
Section 6.3 Assessment
The lowest ionization energy is the ____.
A. first B. second C. third D. fourth

1. A
2. B
3. C
4. D

45
Section 6-3
Section 6.3 Assessment
The first ionization energy will be the smallest
for A. Lithium B. Sodium C. Rubidium D. Hydroge
n

1. A
2. B
3. C
4. D

46
End of Section 6-3
47
Resources Menu
Chemistry Online Study Guide Chapter
Assessment Standardized Test Practice Image
Bank Concepts in Motion
48
Study Guide 1
Section 6.1 Development of the Modern Periodic
Table
Key Concepts

• The elements were first organized by increasing
  atomic mass, which led to inconsistencies. Later,
  they were organized by increasing atomic number.

• The periodic law states that when the elements
  are arranged by increasing atomic number, there
  is a periodic repetition of their chemical and
  physical properties.
• The periodic table organizes the elements into
  periods (rows) and groups (columns) elements
  with similar properties are in the same group.

49
Study Guide 1
Section 6.1 Development of the Modern Periodic
Table (contd.)
Key Concepts

• Elements are classified as either metals,
  nonmetals, or metalloids.

50
Study Guide 2
Section 6.2 Classification of the Elements
Key Concepts

• The periodic table has four blocks (s, p, d, f).

• Elements within a group have similar chemical
  properties.
• The group number for elements in groups 1 and 2
  equals the elements number of valence electrons.
• The energy level of an atoms valence electrons
  equals its period number.

51
Study Guide 3
Section 6.3 Periodic Trends
Key Concepts

• Atomic and ionic radii decrease from left to
  right across a period, and increase as you move
  down a group.

• Ionization energies generally increase from left
  to right across a period, and decrease as you
  move down a group.
• The octet rule states that atoms gain, lose, or
  share electrons to acquire a full set of eight
  valence electrons.
• Electronegativity generally increases from left
  to right across a period, and decreases as you
  move down a group.

52
Chapter Assessment 1
The actinide series is part of the A. s-block
elements. B. inner transition metals. C. non-meta
ls. D. alkali metals.

1. A
2. B
3. C
4. D

53
Chapter Assessment 2
In their elemental state, which group has a
complete octet of valence electrons? A. alkali
metals B. alkaline earth metals C. halogens
D. noble gases

1. A
2. B
3. C
4. D

54
Chapter Assessment 3
Which block contains the transition metals?
A. s-block B. p-block C. d-block D. f-block

1. A
2. B
3. C
4. D

55
Chapter Assessment 4
An element with a full octet has how many valence
electrons? A. two B. six C. eight D. ten

1. A
2. B
3. C
4. D

56
Chapter Assessment 5
How many groups of elements are there? A. 8
B. 16 C. 18 D. 4

1. A
2. B
3. C
4. D

57
STP 1
Which group of elements are the least reactive?
A. alkali metals B. inner transition metals
C. halogens D. noble gases

1. A
2. B
3. C
4. D

58
STP 2
On the modern periodic table, alkaline earth
metals are found only in ____. A. group 1
B. s-block C. p-block D. groups 1318

1. A
2. B
3. C
4. D

59
STP 3
Unreactive gases are mostly found where on the
periodic table? A. halogens B. group 1 and 2
C. group 18 D. f-block

1. A
2. B
3. C
4. D

60
STP 4
Bromine is a member of the A. noble gases.
B. inner transition metals. C. earth metals.
D. halogens.

1. A
2. B
3. C
4. D

61
STP 5
How many groups does the d-block span? A. two
B. six C. ten D. fourteen

1. A
2. B
3. C
4. D