Metallic Bonds

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Metallic Bonds

• Contemorary ChemistryMrs. Coyle

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Metals

• Metals consist of closely packed cations floating
  in a sea of electrons.
• All of the atoms are able to share the electrons.
• The electrons are not bound to individual atoms.

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Cations packed in a sea of electrons
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Properties of Metals

• Good conductors of heat and electricity
• Ductile (able to be drawn into strings)
• Malleable (able to be hammered into sheets)
• Electrons act as a lubricant, allowing cations to
  move past each other
• Metals have a crystalline structure

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The Crystalline Structure of Chromium
Chromium
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The Crystalline Structure of Gold
Gold
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The Crystalline Structure of Zinc
Zinc
http//phycomp.technion.ac.il/pavelba/hcpS.gif
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Alloys

• Mixtures of two or more elements, at least one of
  which is a metal.
• Made by melting, mixing, then cooling the metals.
• May contain non-metals like carbon.

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Alloys

• Properties are superior to their components.
• Sterling silver
• Ag, Cu
• Harder than silver
• Bronze
• Cu to Sn (tin)
• Stainless Steel
• Fe, Cr, C, Ni
• Cast Iron
• Fe, C

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Why is a metal ductile but an ionic compound is
not?