# The Periodic Table by mikesanye

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The Periodic Table
Taking a Closer Look
• Elements can be classified as:
– Metals
– Non-Metals
– Metalloids
Metals
•   Can be moulded and shaped
•   Can be made into a wire  ductile
•   Good conductors of heat and electricity
•   Usually have high melting points
Non-Metals
•   Usually brittle
•   Poor conductors of heat and electricity
•   Dull surface (if solid)
•   Lower melting point
Metalloids
•   Brittle and not ductile
•   May conduct electricity
•   Poor conductors of heat
•   Solids with very high melting points
Table of Properties
State (at room Appearance      Conductivity   Malleability &
temp.)                                        Ductility

Metals          Solid                                      Malleable &
EXCEPT:         Shiny           Good         Ductile
Mercury
Non-         Gas OR Solid
Metals        EXCEPT:           Dull            Poor       Brittle & Not
Bromine                                       Ductile
Metalloids                                  Electricity   Brittle & Not
Solid      Shiny or Dull     maybe          Ductile
Heat  poor
Mercury (metal that is   • Bromine (liquid non-
liquid)                  metal)
Families of Elements
• Just like you and your family the elements
are different but share similar
characteristics
• That is why the periodic table can be
broken down into “families” of elements

Turn to page 220 in your text books
Dimitri Mendeleev (1834-1907)
• The organization of the elements
into the Periodic Table is
credited to Mendeleev, a Russian
Chemist

• His work was accomplished at
a time when little was known
about the atomic structure of matter

• Based on chemical and physical properties, he was able
to group them into families, an arrangement that has
become known as the Periodic Table
An Eye for Pattern
• Mendeleev knew the properties of the elements and
listed them on his element cards

• After he placed them in order of atomic mass,
he noticed patterns

• The properties of a particular element would
be repeated by a heavier element

• He began to rearrange his element cards
placing those elements with similar properties
into columns always increasing mass order
Periodic Law
• Mendeleev stated that:
– When the elements are arranged in order of
increasing atomic mass there is a periodic
repetition of properties
Predicting New Elements
• The genius of Mendeleev is shown by the
use of blank spaces in his periodic table
• Spaces were left in a row because to fill
the spot would break the pattern of the row
Predicting the Elements
Continued..
• Mendeleev suggested that there was an element
(although not yet discovered) to fill the spot
• Two example, Gallium (atomic #31) and
Germanium (atomic #32) are famous for being
discovered shortly after Mendeleev’s prediction
of their existence
• Not only was Mendeleev able to predict their
existence, but he was also able to predict their
properties
The Modern Periodic Table
• Through Mendeleev’s predictions and
ability to see patterns the modern Periodic
Table was developed

• Vertical columns = GROUPS (there are 18
groups or families
• Horizontal rows = PERIODS (there are 7
periods)
Periods – Horizontal rows on the periodic table
Groups – Vertical columns on the periodic table
Groups
• Each group, on the Periodic Table, has similar
characteristics:
– Outer electrons
– Physical properties
– Chemical Properties

• The group names are:
–   Alkali Metals
–   Alkaline Earth Metals
–   Halogens
–   Nobel Gases
–   Hydrogen

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