Download Periodic Table and Chemical Properties

Science 9
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Describe the history of the periodic table
Know the type of information that can be
found on the periodic table
Understand the difference between Metals,
Non-metals and Metalloids
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19th century chemists wanted to organize
their observations of the elements
◦ Wanted to group elements with similar properties
together
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1867 Dmitri Mendeleev made a card for every
known element
◦ He included density, colour, melting
& boiling point
◦ He used these cards to sort and
re-sort until he found a pattern
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Many scientists were trying to organize the
elements
Mendeleev was successful since he realized
there needed to be holes left for
undiscovered elements
Mendeleev was able to predict the properties
of elements that were later discovered from
the placement of the holes and the
surrounding known elements
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Periodic Table contains a lot of information
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Name
Symbol
Atomic number
Atomic mass
Ion charge
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Symbol is generally
the largest piece of
information
Name is usually
written underneath
of the symbol
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Atomic number = the
number of protons
It is always a whole
number (not a decimal
or fraction)
Pattern?
starts at number 1 and
increases in a regular
way down the table
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Mass of average atom
of an element
Measured in atomic
mass units (amu)
Pattern?
Tends to increase
along with atomic
number
*exceptions do occur
ex. Cobalt and Nickel
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Ion charge – electrical
charge that forms on
an atom when it gains
or loses electrons
Some elements have
multiple ion charges
Pattern?
Elements on right side
of table generally
positive. Elements on
the right hand side are
generally negative
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Elements can be categorized into three
groups
◦ 1. Metals
◦ 2. Non-metals
◦ 3. Metalloids
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Metals: typically hard, shiny, malleable,
ductile, and good conductors of heat and
electricity
Non-metals: Do not have the above
properties, generally gases or brittle solids at
room temperature
Metalloids: elements that share some
properties with metals and some properties
with non-metals
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The Periodic table is organized so elements
with similar properties are grouped together.
Where are the metals located?
 Where are the non-metals located
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Ele
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Staircase line starting
next to Boron
Metals are on the left
side of this line
Non-metals (except for
Hydrogen) are located on
the right side of this line
Metalloids are elements
whose box shares a
border with the staircase
line is a metalloid.