Intro to the Periodic table and valence electrons
The Periodic Table
There are 3 main classes of elements: metals,
nonmetals, metalloids.
The Periodic Table
Outline the 3 groups on your Periodic Table:
metals, nonmetals, metalloids.
Metals, Nonmetals, & Metalloids
Divide a piece of
paper as shown
Take notes on
the following
slides
metals
Located on left side of
periodic table
nonmetals
Located on right side of
periodic table
metals
Solids at room temp.
(except mercury)
nonmetals
Most are gases (some
brittle solids)
Metals
higher melting points
nonmetals
lower melting points
metals
nonmetals
malleable
brittle (break easily)
(can be pounded & shaped)
harder
Softer than metals
metals
Ductile
(can be drawn into wire)
nonmetals
Not ductile
metals
lustrous (shiny)
metallic luster mostly
silver or grayish white
nonmetals
dull
metals
Good conductors of heat
and electricity
nonmetals
Poor conductors
(good insulators)
Metals
Tend to lose electrons
form positive ions +
nonmetals
Tend to gain electrons
form negative ions -
Metals
nonmetals
Form ionic compounds
with nonmetals
Form covalent compounds
with other nonmetals
Ionic bonds = transfer of
electrons
Covalent bonds = sharing of
electrons
Metalloids
Have some properties of both metals & nonmetals
Shiny, brittle solids
Limited conductivity
Located along stair step line in between metals &
nonmetals
Uses: semiconductors (Used in electronics), glass, alloys
The Periodic Table
Vertical columns
called groups or families.
Elements in a group have
similar chemical &
physical properties.
Numbered from 1-18
from left to right
Horizontal rows
called periods.
Elements within a
period have properties
that change
progressively across
the table.
The Periodic Table
The group A elements are called the
representative elements.
1A
2A 2A
8A
3A 4A 5A 6A 7A
The Periodic Table
The group B elements are called the transition
elements.
The group B elements at the bottom are called
the inner transition elements.
Transition
Inner
Transition
The Periodic Table
Group 1A Alkali metals
1 valence electron is lost easily, forms a cation (ions
with a positive charge) with a 1+ charge.
The group has similar physical properties
Metallic appearance.
The Periodic Table
Group 2A Alkaline earth metals
2 valence electrons that can be readily lost, forms a
cation with a 2+ charge.
The group has similar physical properties
Metallic appearance.
The Periodic Table
Group 7A Halogens (nonmetals)
highly reactive with 7 valence electrons, forming an
anion (a negatively charged ion) with a 1- charge
The Periodic Table
Group 8A noble gases
have a complete octet (8) of valence electrons
they have little tendency to gain or lose electrons
and are non-reactive.
The Periodic Table
Group B transition metals
in the middle of the Periodic Table
Number of outer electrons varies, leading to a
variety of charges for each element.
they share many of their chemical and physical
properties
The Lanthanide series and the Actinide series,
located at the bottom of the periodic table, are the
inner transition metals (the rare earth metals).
Noble
Gas
Inner Transition Metals
(f – block elements)
Metalloids
(on the stair-step line)
The Periodic Table
Label the following families on your Periodic
Table
Valence Electrons – outer electrons
The A group number = the number of
valence electrons (except for He)
1A
8A
2A
3A 4A 5A 6A 7A
Valence electrons = the # of dots for Lewis Dot Diagrams
Lewis Dot Diagrams
The electron structure of an atom determines many
of its chemical & physical properties. For the group A
elements, the group number equals the number of
valence electrons.
(Except for Helium = 2) •He•
Fill in the element symbols and valence electrons on
the blank Periodic table
Using the Internet or a borrowed Chemistry
class set of books research and create the
assigned Periodic Families Poster
Students will complete the worksheet
summarizing the information found on each
poster.
Complete the Stemscopes Periodic Table
Activity
Make flash cards of the elements and
polyatomic ions using either index cards,
notebook paper or construction paper
Re-write the list by grouping all of the ones with
similar charges together.
Study with a partner for your quiz tomorrow.
(You may use a Periodic table on the quiz)