Transcript periodic trends

Catalyst – February 30-4, 2013
HW OUT PLEASE!
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1.
2.
3.
4.
5.
6.
Using the PT, choose and record an element from
each of the following groups:
Alkali Metals
Transition Metals
Noble Gases
Anctinides
Metalloids
Halogens
Our Periodic Table – Thanks to Mosely
Today’s Agenda
(FYI: Quizzes back tomorrow)
Catalyst
 HW Questions?
 Notes: Periodic Trends
 PT Trends Work CUZ WE RIDIN NERDY!
 Project Work Time
 Exit Question, Lab Fees, and Progress Reports!
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HOMEWORK:
PERIODIC TRENDS WORKSHEET
Periodic Table Project
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Will choose an element from the list provided
No one can have the same element!
Part 1: Element Card for the wall (25 Points)
Part 2: Element Facebook Page (75 Points)
Cool Source! YouTube Periodic “Table of Videos”
HAPPY NERD DAY!!!!
HW Questions???
Today’s Objectives
SWBAT define periodicity.
 SWBAT describe the periodic trends
for valence electrons, atomic radius,
and electronegativity.

NOTES TITLE:
PERIODICITY AND PERIODIC
TRENDS
CHEMISTRY
& YOU
How are trends in the weather similar to
trends in the properties of elements?

Although the weather
changes from day to
day, the weather you
experience is related
to your location on the
globe.
Copyright © Pearson Education,
Inc., or its affiliates. All Rights
Reserved.
.
Periodicity is…
Key Point #1: Periodicity is
the quality or state of being
regularly recurrent or
having periods.

Periodic Trends
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Key Point 2: The trends and
patterns on the periodic table
help us both compare and
contrast elements.
Note-Taking Strategy

Use the chart in your notes – like this….
Vocab Word
Periodic Trend
Nab that Vocab!
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1.
2.
3.
Copy your definitions from yesterday into the
table in your notes! Repeated writing may help
you remember the definitions!
Valence electrons: ???
Atomic radius: ???
Electronegativity: ???
Note-Taking Strategy

Use the chart in your notes – like this….
Vocab Word
Periodic Trend
Valence electrons: ???
Atomic radius: ???
To be filled in!
To be filled in!
Electronegativity: ???
To be filled in!
Note-Taking Strategy

Use the chart in your notes – like this….
Vocab Word
Periodic Trend
Valence electrons: electrons in
the outermost (or
outside/biggest) energy level
Atomic radius: ???
To be filled in!
To be filled in!
Electronegativity: ???
To be filled in!
Note-Taking Strategy

Use the chart in your notes – like this….
Vocab Word
Periodic Trend
Valence electrons: electrons in
the outermost (or
outside/biggest) energy level
Atomic radius: how big an
atom is, also known as atomic
size
To be filled in!
To be filled in!
Electronegativity: ???
To be filled in!
Note-Taking Strategy

Use the chart in your notes – like this….
Vocab Word
Periodic Trend
Valence electrons: electrons in
the outermost (or
outside/biggest) energy level
To be filled in!
Atomic radius: how big an
atom is, also known as atomic
size
To be filled in!
Electronegativity: the ability of
an atom to attract electrons to
itself in a chemical bond; how
much an atom wants electrons
To be filled in!
LOOK OUT!
VALENCE ELECTRONS
TREND
Let’s look at Bohr Models…
http://www.chemicalelements.com/show/electronconfig.html

TREND: Valence Electrons
# of valence electrons
increases from 1-8 as you go
left to right (#A on top of PT)
1------------------------------------>8

Valence Electrons Write on your PT
LOOK OUT!
ATOMIC RADIUS
TREND
Ranked Small to Large:
Na, K, Rb, Cs
LOOK OUT!
ELECTRONEGATIVITY
TREND
Ranked Small to Large:
Ga, Ge, As, Se
Electronegativity Values for Selected Elements in Paulings
H
2.1
Li
1.0
Be
1.5
B
2.0
C
2.5
N
3.0
O
3.5
F
4.0
Na
0.9
Mg
1.2
Al
1.5
Si
1.8
P
2.1
S
2.5
Cl
3.0
K
0.8
Ca
1.0
Ga
1.6
Ge
1.8
As
2.0
Se
2.4
Br
2.8
Rb
0.8
Sr
1.0
In
1.7
Sn
1.8
Sb
1.9
Te
2.1
I
2.5
Cs
0.7
Ba
0.9
Tl
1.8
Pb
1.9
Bi
1.9
Using Graphs to
Understand
the Relationship Between
Atomic Radius and
Electronegativity
GROUP 1
H + Alkali Metals
300
250
200
150
100
50
0
0
1
2
3
4
5
6
7
Element
2.5
2
Electronegativity
Atomic Radius (picometer)
350
1.5
1
0.5
0
0
1
2
3
4
Element
5
6
7
8
PERIOD 1
Li - Ne
4
3.5
3
2.5
2
1.5
1
0.5
0
0
2
4
6
8
Element
160
Atomic Radius (picometer)
Electronegativity
4.5
140
120
100
80
60
40
20
0
0
2
4
6
Element
8
10
Why is this relationship true?
vs.
LARGE EN
=
SMALL AR
LARGE AR
=
SMALL EN
Work Time
Complete worksheet from Ms.
Stroh 
 Help each other and ask questions
when you’re all stumped!
 When you finish, you may work
on your Periodic Table Project 

Exit Question
1.
2.
3.
State the left to right trend for valence
electrons.
Which element has the largest atomic
radius: Ag, Cu, Hg, or Zn?
Which element has the largest
electronegativity: Ag, Cu, Hg, or Zn?
HOMEWORK:
PERIODIC TRENDS WORKSHEET