Chapter 7: Ionic and Metallic Bonding

Section 3: Bonding in Metals

Metallic Bonds and Metallic Properties

• Metals – closely packed ________ in a sea of

_________.

• Metallic bond– Positive __________ are attracted to the

negative ___________.– Attraction holds the metal together

Metallic Bonds and Metallic Properties

• “____ of electrons” – allows the metal

___________ to move freely past each other

– gives metals their ______________.

Metallic Bonds and Metallic Properties

• Properties– Good conductors- electrons

can _______ ___________– Ductile (drawn into wires)-

electrons and cations can be __________

– Malleable (hammered or forced into shapes)- _____________ at one end of a piece of metal and be forced to the other

Practice

• What do ionic bonds and metallic bonds have in common?

• What are the differences between ionic and metallic bonds?

• What will happen to a metal if struck with a hammer?

• What will happen to an ionic crystal if struck with a hammer?

Crystalline Structure of Metals

• Metals are considered ____________ – arranged in a very orderly, __________

pattern

• Several possible arrangements of metal ____________

Crystalline Structure of Metals

• Body-centered cubic– ________neighbors – Ex: sodium,

_________, iron, chromium, _________

Crystalline Structure of Metals

• Face centered cubic– ____ neighbors – Silver, gold,

________, aluminum, ________

Crystalline Structure of Metals

• Hexagonal close packed– ___ neighbors, but

different from _____ __________

– magnesium, _____, and cadmium

Alloys• Mixtures of two or ________ _____________,

one must be a _________• More useful than their __________ __________• Examples

– Cast Iron (Fe + _____)– Sterling silver (Ag + ______)– Bronze (Cu + ______)– Steel (Fe + _____)

• stainless• spring • surgical

– titanium alloys (Ti + others)