Q. Which of the following is a non-stoichiometric defect?
(c)metal deficiency defect
Answer: (c)metal deficiency defect (anion is missing from lattice site)
In Frenkel defect the smaller ion occupies the interstitial sites and Schottky defect equal number of cations and anions are missing. Interstitial defect an atom or molecule occupies intestinal sites so in these three defects the ratio of positive and negative ions (Stoichiometric) of a solid is not disturbed in these three