*8 *** (a) a substance ab, crystallizes in an fec lattice in which atoms a occupy each corner of the cube and atoms b occupy the centres of each face of the cub

*8 *** (a) A substance AB, crystallizes in an fec lattice in which atoms A OCcupy each corner of the cube and atoms B occupy the centres of each face of the cube. What will be the correct formula of the substance r b) A group 13 element is added in small amounts to Ge crystal. The doped crystal acts as -semiconductor. (FUl up the gap) Contd. (c) What is the unit of flocculation value of a coagulating electrolyte ? (d) What happens when a freshly precipitated Fe (OH)3 is shaken with little amount of dilute solution of FeCl ? Give reaction. (e) The weight average molecular weight of a polymer is 29,000. If the polydispersity index of the polymer is 0:7, what will be its number average molecular weight ? U) If 2 is the partition function and what will be the average energy ot the system ? (g) The formation of micelles takes place above a particular temperature called (Fll up the gap)