1.3 Classify the following as amorphous or crystalline solids:

Polyurethane, naphthalene, benzoic acid, Teflon, potassium nitrate, cellophane, polyvinyl chloride, fibreglass, copper. 


Amorphous solids
Polyurethane, Teflon, cellophane, polyvinyl chloride, fibreglass
Crystalline solids
Naphthalene, benzoic acid, potassium nitrate, copper