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Metallic bonding Topi c 4.4. YouTube video 1:21. valence electrons detach from individual atoms since metals contain only 1-3 valence electrons no particular electron is confined to a particular metal atom
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Metallic bonding Topi c 4.4 YouTube video 1:21
valence electrons detach from individual atoms since metals contain only 1-3 valence electrons • no particular electron is confined to a particular metal atom • leaves a close packed lattice of positive ions (cations) in a sea of delocalized negative electrons • the electrostatic attraction between the cations and sea of electrons holds the metal together • electrons act as a "glue" giving the substance a definite structure
when the metallic atom becomes bigger, the sea of negative electrons becomes farther away and harder for nuclei to hold on to • therefore, melting point decreases as you go down period one the table (or any metal for that mater)
the delocalized nature of the bonds, make it possible for the atoms to slide past each other • this means metals are malleable and ductile • hammered into thin sheets or shapes without breaking • drawn into wires • ionic compounds would crack • metals are essential part of the world economy • reinforcement of concrete, wires, cars, pipes… • traded as commodities • most common is iron which is in steel