Crystalline solids are 'anisotropic' comment.

Crystalline solids are not true solids. Why?

Why are solids rigid?

Classify the following as amorphour or crystalline solids: Polyurethane, nephthalene, benzoic, acid, teflon, potassium nitrate, cellphane, polyviny chloride, fibre glass, copper.

Sodium form a crystalline ionic solid with dihydrogen. The solid is non-volatile and non-conducting in nature. It reacts violectly with water to produce dihydrogen gas. Write the formula of this compound and its reaction with water. What will happen on electroysis of the melt of this solid?

Both growth and differentiation in higher plants are open'. Comment.

Amorphous solids are not true solids . Explain .