Q20 of 68 Page 29

What type of stoichiometric defect is shown by?

(i) ZnS (ii) AgBr

i) ZnS shows Frankel defect


Explanation: Frankel defect arises when an atom or smaller ion leaves its place in the lattice, creating a vacancy and becomes an interstitial by lodging in a nearby location. This occurs in ZnS due to the comparatively smaller size of Zn2+ .


ii) AgBr shows frankel as well as schottky defect.


Explanation: AgBr shows both types of defects, i.e. schottky and Frenkel Defects. Since, Schottky Defects arises because of mission of constituent particles, thus it decreases the density of ionic compound.


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