The Periodic Table
The Organization of the Periodic Table
• The Periodic Table of Elements is organized by
Atomic number
(the number of PROTONS in an element)
• Dmitri Mendeleev ( 1834- 1907) created the
periodic table of elements
• The Periodic Table of Elements is a visual
presentation of the elements in groups
according to their physical and chemical
properties.
The Periodic Table of ElementsColumns
• The table has been organized by the number of
VALENCE electrons ( Electrons in the outer most
energy level)
• The table has also been organized into columns
or FAMILIES ( up and down)
• Each FAMILY contains elements with the same
number of VALENCE electrons
• The amount of VALENCE electrons determines
their chemical properties... How they are going to
react
Groups and Families of the Periodic
Table
• How many VALENCE electrons does Lithium
(Li), Sodium (Na) and Potassium (K) have?
• They belong to the same group/family
because they all have one valence electron
Family Names
• Certain groups/families have specific names
• We have the
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Alkali Metals
Alkaline Earth Metals
Halogens
Noble Gases
The Alkali Metals
• All elements in the first column EXCEPT
hydrogen
• (Li, Na,K, Rb, Cs,Fr)
• Characteristics of ALKALI metals
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These elements all have 1 VALENCE electron
These elements are all shiny and soft metals
These elements will react with water EXPLOSIVELY!!
Because of their high reactivity these elements are not
found in their elemental state but instead exist as
COMPOUNDS
The Alkaline Earth Metals
• All elements in the second column
• (Be, Mg, Ca, Sr, Ba, Ra)
• Characteristics of Alkaline Earth Metals
• These elements all have 2 valence electrons
• These elements are highly malleable and reactive and
they burn easily in the presence of heat
• Because of their high reactivity these elements are not
found in their elemental state but instead exist as
COMPOUNDS
• They form many compounds found in rocks and earth…
The Halogens
• All Elements in the second to last column
(Group 7)
• Characteristics of Halogens
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These elements have 7 VALENCE electrons
These elements are all non-metals
The word HALOGEN means “salt-former”
All compounds that contain Halogen elements are
called SALTS ex: NaCl
• Halogens also kill germs when they are dissolved in
water
The Noble Gases
• All elements in the last column ( Group 8)
• Characteristics of Noble Gases
• These elements are special because their outer energy
shell is completely full
• These elements will not easily combine with other
elements to form compounds
• When electricity is passed through these gases, light is
released and these gases are often used in lights.
• Argon comes from the Greek argos, meaning “lazy” or
“inactive”
The Periodic Table of Elements
• All of the elements can be classified into three
categories
1) Metals
2) Non- Metals
3) Metalloids
• The staircase shaped line that crosses the
right side of the table helps to locate and
identify these categories
Metals
• Good conductors of electricity and heat
• Often ductile and malleable which means they
are easily made into wires or flattened into
sheets... THINK ALUMINUM FOIL...
• Usually shiny
• All METALS are solid at room temperature
except MERCURY which is liquid
• Many Metals react with Acids
• Found to the LEFT of the STAIRCASE on the
Periodic Table
Non- Metals
• Poor conductors of electricity and heat
• Many non-metals are gases at room
temperature
• The solid non-metals can easily be made into
powders
• Found to the RIGHT of the STAIRCASE
• Except for HYDROGEN
Metalloids
• Seven elements with properties of both
METALS and NON-METALS
• Ex: Some METALLOIDS are good conductors of
electricity and some are poor conductors depending
on conditions
• METALLOIDS are found on both sides of the
staircase
Activity
• On your Periodic Table
• Label and define the parts of the periodic table
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–
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Square
Atomic Number
Group
Staircase
• Color in the metals, non-metals and
metalloids each in a different color