What are metallic crystals ?

What are ionic crystals ? Discuss the crystal structure of sodium chloride.

What are molecular crystals ? Name the forces which are holding the constituent particles in molecular crystals.

A metal crystallises in a face centred cubic structure. If the edge length of its unit cell is 'a' the closest approach between two atoms in metallic crystal will be

What is an ideal crystal ? Name the types of the defects which arise in a crystal.

What type of stoichiometric defects are noticed in crystals?

What are metal excess defects in crystals ? How are these caused ?

What are piezoelectric crystals ? Give their important uses.

When heated above 916^(@)C , iron changes, its crystal structure from body centred cubic to cubic closed packed structure. Assuming that the metallic radius of an atom does not change, calculate the ratio of the density of the bcc crystal to that of ccp crystal.

if a metal has a bcc crystal structure, the coordination number is 8,because :

The metal M crystallizes in a body centered lattice with cell edge. 400 pm. The atomic radius of M is