Transcript Periodic Trends - The Green Isle

Rally-Table
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Write out the Electron Configuration for
the following elements
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Li
Mg
B
C
P
S
F
Ar
Periodic Trends and
Organization
Essential Question: How does the periodic
table organize the elements according to
their atomic structure and chemical
reactivity?
Get out your handout of the periodic table
Ionization Energy
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The amount of energy required to remove an
electron from an atom or ion.
• (to become a cation)
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IE depends on the average electron distance from
the nucleus and the attraction of the nucleus.
Why do you think the distance between the
valence electrons and the nucleus determines the
amount of energy required to remove electrons
from the atom?
Ionization Energy
•Ionization energy
decreases as you
move down a group
and increases as
you move up a
group.
•The farther down
you go down the
more reactive the
element.
•Ionization energy increases across a period.
•Make an inference as to why you think this is so.
Atomic Radii: Size of the atom
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Atomic radii increases down a group.
Atomic radii decreases across a
period (left  right)
Electronegativity
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The ability of an atom to attract electrons.
The higher the electronegativity, the more
strongly an atom attracts electrons.
row
Summary of all Periodic Trends
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Electronegativity
Electronegativity
S
Numbered Heads Together:
Applying the Trends
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Based on what we know about Ionization energy and how it
changes as you move through the periodic table, Predict
which element on the periodic table is the most reactive?
Is it a metal or a nonmetal?
Based on what we know about Electronegativity and its
trends across the table, predict which element is the most
reactive?
Is it a metal or non metal?
Drawing conclusions: Which element is the most reactive
metal and which is the most reactive nonmetal on the
periodic table?
Numbered Heads Together
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Based on the trends, which element should be
the largest and which should be the smallest?
Using the trends, explain why some elements
will tend to gain electrons while some will tend
to lose electrons when forming ions.
Drawing conclusions: Which atoms will become
anions and which will become cations?
http://www.webelements.com/
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This is a neat site for information on
any element in the periodic table.