ChemistryChemistry

Bonding in MetalsBonding in Metals You have probably You have probably

seen decorative seen decorative fences, railings, or fences, railings, or weathervanes weathervanes made of a metal made of a metal called wrought iron. called wrought iron. In this section, you In this section, you will learn how will learn how metallic properties metallic properties derive from the way derive from the way that metal ions that metal ions form bonds with form bonds with one another.one another.

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Metallic Bonds and Metallic Metallic Bonds and Metallic PropertiesProperties

Metallic Bonds and Metallic Metallic Bonds and Metallic PropertiesProperties

How can you model the How can you model the valence electrons of metal valence electrons of metal atoms?atoms?

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Metallic Bonds and Metallic Metallic Bonds and Metallic PropertiesProperties

The valence electrons of metal The valence electrons of metal atoms can be modeled as a sea atoms can be modeled as a sea of electrons.of electrons.

The valence electrons are mobile The valence electrons are mobile and can drift freely from one part of and can drift freely from one part of the metal to another.the metal to another.Metallic bonds consist of the Metallic bonds consist of the attraction of the free-floating valence attraction of the free-floating valence electrons for the positively charged electrons for the positively charged metal ions.metal ions.

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Metallic Bonds and Metallic Metallic Bonds and Metallic PropertiesProperties

Metals are Metals are ductile—that is, ductile—that is, they can be they can be drawn into drawn into wires.wires.

7.3

Metallic Bonds and Metallic Metallic Bonds and Metallic PropertiesProperties

A force can change the shape of a A force can change the shape of a metal. A force can shatter an ionic metal. A force can shatter an ionic crystal.crystal.

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Crystalline Structure of MetalsCrystalline Structure of Metals

Crystalline Structure of MetalsCrystalline Structure of Metals

How are metal atoms arranged?How are metal atoms arranged?

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Crystalline Structure of MetalsCrystalline Structure of Metals

These tomatoes These tomatoes have a closed-have a closed-packed packed arrangement. arrangement. Similar Similar arrangements arrangements can be found in can be found in the crystalline the crystalline structure of structure of metals.metals.

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Crystalline Structure of MetalsCrystalline Structure of Metals

Metal atoms are arranged in very Metal atoms are arranged in very compact and orderly patterns.compact and orderly patterns.

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AlloysAlloys

AlloysAlloys

Why are alloys important?Why are alloys important?

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AlloysAlloys

AlloysAlloys are mixtures are mixtures composed of two or more composed of two or more elements, at least one of elements, at least one of which is a metal.which is a metal.

Alloys are important because Alloys are important because their properties are often their properties are often superior to those of their superior to those of their component elements.component elements.

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AlloysAlloysBicycle frames are often made of Bicycle frames are often made of titanium alloys that contain titanium alloys that contain aluminum and vanadium.aluminum and vanadium.

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AlloysAlloys

The most important The most important alloys today are alloys today are steels. Steels have steels. Steels have a wide range of a wide range of useful properties, useful properties, such as corrosion such as corrosion resistance, resistance, ductility, hardness, ductility, hardness, and toughness.and toughness.

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7.3 Section Quiz. 7.3 Section Quiz.

7.3.7.3.

1.1. The valence electrons of metals The valence electrons of metals can be modeled ascan be modeled as

a body-centered cube.a body-centered cube. octets of electrons.octets of electrons. a rigid array of electrons.a rigid array of electrons. a sea of electrons.a sea of electrons.

7.3 Section Quiz.7.3 Section Quiz.

2. 2. In most metals, the atoms areIn most metals, the atoms are free to move from one part of the metal to free to move from one part of the metal to

another.another. arranged in a compact and orderly pattern.arranged in a compact and orderly pattern.

placed at irregular locations.placed at irregular locations. randomly distributed.randomly distributed.

7.3 Section Quiz.7.3 Section Quiz.

3. 3. Alloys are important because theyAlloys are important because they are pure substances.are pure substances. are the ores from which metals can be are the ores from which metals can be

refined.refined. can have properties superior to those of can have properties superior to those of

their components.their components. are produced by the combustion of metals.are produced by the combustion of metals.

7.3 Section Quiz.7.3 Section Quiz.

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