Classify the following as amorphous or crystalline solids: Polyurethane, naphthalene, benzoic acid, teflon, potassium nitrate, cellophane, polyvinyl chloride, fibre glass, copper.


SUBSTANCE



TYPE OF SOLID



Polyurethane



amorphous solid



Naphthalene



crystalline solid



Benzoic acid



crystalline solid



Teflon



amorphous solid



Potassium nitrate



crystalline solid



Cellophane



amorphous solid



Polyvinylchloride



amorphous solid



Fibre glass



amorphous solid



Copper



crystalline solid




Explanation: Amorphous solids are not true solids, in these solids the constituent particles (atoms, ions or molecules) have short range order of arrangement.


In crystalline solids the constituent particles have long range order of arrangement)


6