Which of the following stoichiometic defect results in the increase in the density of the crystalline substance.

Options

A. Frenkel defect
B. Schottky defect
C. Interstitial defect
D. Vacancy defect

Answer

4

Explanation

When some constituent particles (atoms or molecules) in nonionic solids are presernt in the interstitial sites ,the crystal is said to have interstital defects,.
This defect results in the increase in the density of the substnace because mass increase but volume remains the same . The density of a defect lattice should be different from that of a perfect lattice. The presence of 'holes' should lower the density but if there are too many holes there may be a partical collapse or distrotion of the lattice -in which case the density is unpredictable.The presence of ions in interstitial positions may distort (expand) the lattice and increase the unit cell dimensions.