Types Of Solids (20 Min) - amorphous, crystalline, metallic, covalent, ionic 

Amorphous structures have no real repeating pattern thereby not having a unit cell. Crystalline structures do have a unit cell and therefore have a specific shape. Crystalline structures consist of metallic, molecular, covalent network and ionic bonds. The outdated notion that all covalently bonded molecules do not conduct heat or electricity is incorrect since there are exceptions as a result of pi bond characteristics.
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