Frenkel defect does not change the density of the ionic crystal whereas, Schottky defect lowers the density of ionic crystal. Give a reason.

Explanation

Frenkel defect arises due to the presence of holes in the cationic lattice site and cation occupies an interstitial position. Hence density remains the same, whereas Schottky defect arises when same number of cations and anions are missing from their normal site and a pair of holes are formed hence density decreases.