Which is the incorrect statement ?

1.	Which is the incorrect statement ?
Answer» `FeO_0.98` has non-stoichiometric metal deficiency DEFECT Density decreases in case of crystals with Schottky's defect NaCl(s) is insulator , SILICON is semiconductor, SILVER is conductor , quartz is piezoelectric crystal Frenkel defect is favoured in those ionic compounds in which the sizes of cations and ANIONS are almost equal Solution :Non-stoichiometric ferrous oxide is `Fe_(0.93-0.98) O_1.00` ( and not `FeO_0.98`) which is DUE to metal deficiency defect. Hence, (a) is incorrect. Frenkel defect is favoured in those ionic compounds in which sizes of cation and anion are largely different . Hence (d) is incorrect.

Discussion