(a) From the following choose the incorrect statement about crystalline solids.
(i) Melt at sharp temperature.
(ii) They have definite heat of fusion.
(iii) They are isotropic
(iv) They have long range order.
(b) Cubic unit cells are divided into primitive, bcc and fee.
(i) Calculate the number of atoms in a unit cell of each of the following:
* bcc
* fcc
(ii) Write two examples for covalent solids.
