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Explore the essential role of metallic bonding in metals found in the periodic table, from their unique properties to the formation of alloys. Learn how the delocalized electrons in metallic bonds contribute to high conductivity, malleability, and ductility in metals.
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Properties of Metals • Solids (except Hg) – most have high mp & bp • Luster • Malleable & ductile • Good conductor of heat & electricity • Metals are losers! (metals lose electrons and form positive ions) • Low ionization energy • Low electronegativity
Metallic Bonding Metal atoms form a lattice. The valence levels of the atoms overlap. The valence electrons can roam easily from 1 atom to another throughout the metal. Metallic bonding
Delocalized Electrons • Valence electrons are free to roam throughout crystal • “Sea of Mobile Electrons” • Metallic Bond = attraction between positive metal kernel and electron sea.
Comparison of Metallic & Ionic Bonding Lattice points are all positive. Electrons roam. Lattice points are positive and negative.
Properties of metals • Electrons can move so they conduct a current. • Electron sea holds the metal together when it’s deformed.
Metallic Bonds • Pretty strong. All metals but Hg are solids at room temperature. • Most have moderately high melting points & high boiling points.
Deformation of Metals Deformation of Metals
Deformation of Metals • Applied force moves metal cations. • Cations are held together by electron sea.
Alloys • Mixture of elements that has metallic properties. • Adjust the mixture to get desired properties. • Can be substitutional or interstitial
Substitutional Interstitual Types of Alloys Steel Bronze Brass