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Explain Schottky defect. |
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Answer» Solution :Schotky defect arises due to the missing of equal mumber of cations and anions from the crystal lattice.This effect does not change the stoichiometry of the crystal. lonic solids in which the cation and ANION are of almost of similar size show SCHOTTKY defect. Example : `NaCl`. Presence of large number of schottky defects in a crystal, lowers its DENSITY. For example, the theoretical density of vanadium MONOXIDE (VO) calculated using the edge length of Schottky Defect the unit cell is `"6.5 g cm"^(-3)`, but the actual experimental density is `"5.6 g cm"^(-3)`. It indicates that there is APPROXIMATELY `14%` Schottky defect in VO crystal. Presence of Schottky defect in the erystal provides a simple way by which atoms or ions can move within the crystal lattice. 
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