Section 6.4 Metallic Bonding =The Sea of Electron...
Transcript of Section 6.4 Metallic Bonding =The Sea of Electron...
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Section 6.4Metallic Bonding
=The Sea of Electron Model=
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Section 6.4Metallic Bonding
=The Sea of Electron Model=
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Recall, metals form only positive ions...
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Recall, metals form only positive ions...This is because they have a weak hold onto their valence electrons.
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Consequently, all metal solid contain a "sea of electrons"
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Consequently, all metal solid contain a "sea of electrons"(aka, delocalized electrons)
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Consequently, all metal solid contain a "sea of electrons"(aka, delocalized electrons)
that surround the metal cations.
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Metallic bond: the attraction between the metal cations and
the sea of electrons.
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This is why metals can be deformed without breaking...
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This is why metals can be deformed without breaking...
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This is why metals can be deformed without breaking...
the sea of electrons movewith the deformation!
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Properties of metals:
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Properties of metals:•Good conductors of heat and
electricity.
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Properties of metals:•Good conductors of heat and
electricity.•Malleable (can be reshaped).
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Properties of metals:•Good conductors of heat and
electricity.•Malleable (can be reshaped).•Ductile (can be drawn into
wires).
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Properties of metals:•Good conductors of heat and
electricity.•Malleable (can be reshaped).•Ductile (can be drawn into
wires).•Lustrous (shiny; electrons
absorb and re-emit light)
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Properties of metals:•Good conductors of heat and
electricity.•Malleable (can be reshaped).•Ductile (can be drawn into
wires).•Lustrous (shiny; electrons
absorb and re-emit light)•High melting and boiling points.
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Q: Why are group 1 and 2 metals soft, but most of the transition metals quite hard?
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Transition Metals
Number of delocalized electrons
Group 2 MetalsGroup 1 Metals
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Transition Metals
Number of delocalized electrons
Soft Group 2 MetalsGroup 1 Metals
Hard
Very Soft
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1
Transition Metals
Number of delocalized electrons
Soft Group 2 MetalsGroup 1 Metals
Hard
Very Soft
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21
Transition Metals
Number of delocalized electrons
Soft Group 2 MetalsGroup 1 Metals
Hard
Very Soft
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2+21
Transition Metals
Number of delocalized electrons
Soft Group 2 MetalsGroup 1 Metals
Hard
Very Soft
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2+21
Transition Metals(also smaller!)
Number of delocalized electrons
Soft Group 2 MetalsGroup 1 Metals
Hard
Very Soft
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Alloy:
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Alloy: A mixture of metallic elements, held together by metallic bonds.
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Examples