Identify the incorrect statement regarding crystals having Frenkel defect.
Identify the incorrect statement regarding crystals having Frenkel defect.
Frenkel defects are observed where the difference in sizes of cations and anions is large.
The density of crystals having Frenkel defect is less than that of a pure perfect crystal.
An ionic crystal having Frenkel defect may also contain Schottky defect.
Alkali halides do not usually have Frenkel defect.
Solution
In Frenkel defect density remain constant. It is a defect of a cation or an anion is dislocated from its normal site to interstitial site. Interstitial site is the place between the lattice sites.
This defect is observed in solids when the difference in ionic radius of two ions is very large.
Hence, the density of crystals having Frenkel defect is less than that of pure perfect crystal.