Transcript Periodic trends - Menchville Chemistry

PERIODIC TRENDS
L
Minilab
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Pg 164
Use graph paper on center counter
No lab write up required
 Answer
analysis questions on graph paper
 Show me completed product
Molar Heat of Fusion
Molar Heat of Vaporization
120
800
C
700
C
100
600
80
Be
500
60
400
Be
Si P
Si
300
Be
Al
40
200
Li
20
100
Al
Mg
Be
Li
0
0
Na O F Ne Na
5
10
Mg
Na
Cl
P Si
15
Ar
0
20
0
NaO F Ne
5
10
Si Cl Ar
15
20
800
C
700
600
Be
500
400
Si
Hf
P
Hv
300
Be
Al
200
Li
Mg
C
100
Na
Be
Be
Li
0
0
Si
2
O
O
Na
Na
4
6
FF
Ne
8
Mg
Na
10
Al
Si
Si
P
12
14
Cl
Cl
Ar
Ar
16
18
Atomic Radius
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Remember: e- cloud is a probability
Has no defined edge
 Outer limit = 90% of finding an e- inside
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Atomic size – how close an atom lies to it’s neighbor
For metals = half the distance b/t adjacent nuclei
 For non-solids = half the distance b/t nuclei of identical
atoms bonded together chemically
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Decreases as you move across the period
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Why?
Increases as you move down families
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Why?
Generally Increases
Generally Decreases
Your book is lame…
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Ions
 e-
are negatively charged
 Atoms that gain or lose 1+ gain a net charge
 Gains and losses are always in the valence shell
 Ion = +/- atom or bonded group of atoms
Ionic Radius
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What would a positive charge do to the atomic radii?
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What would a negative charge do to the atomic radii?
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Periods
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Decrease till you get to group 5
Families
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Increase as you go down the periodic table
MINI DEMO
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Moo-licious
Ionization energy
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Energy needed to remove a curtain # of e- from an
atom’s valence shell
1st ionization energy
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Periods
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Families
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Decreases
Why? What has the greatest 1st ionization energy?
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Increases
NOBLE GASES!!!
Octet rule: Atoms will gain/lose e- to become more stable
and have a perfect octet (like a noble gas)
Electronegativity
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Ability of an atom to attract e- in a chemical bond
 Noble
gases aren’t part of this b/c they don’t react
readily with anything
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Higher electronegativity pulls more on the e-
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Periods
 Increases
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from left to right
Families
 Decreases
going down
My name is Fluorine.
Ryan Seacrest is gay.
Paula is stupid.
You should never sing again.
I once was in a band.
That will be $15 Million.
F
Oh Francium, I feel
we can share
anything
I very much agree. By the
way, Cesium, thanks for
letting me borrow your
shoes.
I have shoes? Where?
Which orbital??
My crutch
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Youtube take it home