Tonight

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Tonights Homework
Read section 9.1 and do problem 12 on page 247.
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Covalent Bonds
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Covalent Bonds
The positive nucleus of one atom attracts the
negative electrons of the other atom.
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Covalent Bonds
The atoms move closer.
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Covalent Bonds
If they get too close, the positive nuclei repel
each other.
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Covalent Bonds
There is a balance point where the attraction and
the repulsion cancel out.
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Covalent Bonds
Atoms will stay at this balance point. They have
a stable bond. They are a molecule.
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Covalent Bonds
Atoms in a covalent bond dont give away
electrons or take them from other atoms. In a
covalent bond, atoms share electrons.
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Covalent Bonds
F F Both atoms want one more
electron.
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Covalent Bonds
F F They can share these two.
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Covalent Bonds
F F Now both atoms are happy.
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Covalent Bonds
F F This atom has eight outer electrons.
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Covalent Bonds
F F So does this one.
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Covalent Bonds
F F A dot diagram for a molecule is called a
Lewis structure
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Covalent Bonds
F-F The pair of shared electrons can be drawn
as a line.
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Covalent Bonds
O O Oxygen wants two more electrons.
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Covalent Bonds
O O Theyll share this pair...
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Covalent Bonds
O O and this pair.
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Covalent Bonds
O O Oxygen atoms share two pairs of electrons.
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Covalent Bonds
O O Again, both atoms seem like they have
eight outer electrons.
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Covalent Bonds
O O Again, both atoms seem like they have
eight outer electrons.
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Covalent Bonds
OO They have a double bond, which can be drawn
as two lines.
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Covalent Bonds
N N Nitrogen wants three more
electrons.
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Covalent Bonds
N N Nitrogen wants three more
electrons.
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Covalent Bonds
N N A nitrogen molecule has a triple bond.
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Covalent Bonds
NN A nitrogen molecule has a triple bond.
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Covalent Bonds
H Hydrogen often forms covalent bonds with
other elements.
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Covalent Bonds
H O H Hydrogen often forms covalent
bonds with other elements.
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Covalent Bonds
H O H Hydrogen often forms covalent
bonds with other elements.
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Covalent Bonds
H-O-H Hydrogen often forms covalent bonds with
other elements.
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You try some!
Draw the Lewis structure for the molecule PH3
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You try some!
Draw the Lewis structure for the molecule H-P-H H
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You try some!
Draw the Lewis structure for the molecule H2S
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You try some!
Draw the Lewis structure for the molecule H-S-H
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You try some!
Draw the Lewis structure for the molecule HCl
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You try some!
Draw the Lewis structure for the molecule H-Cl
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You try some!
Draw the Lewis structure for the molecule CCl4
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You try some!
Draw the Lewis structure for the
molecule Cl Cl-C-Cl Cl
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You try some!
Draw the Lewis structure for the molecule SiH4
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You try some!
Draw the Lewis structure for the
molecule H H-Si-H H
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Tonights Homework
Read section 9.1 and do problem 12 on page 247.