$ZnO$ shows yellow colour on heating due to:

Explain stoichiometric defects shown by non-ionic solids.

The correct statement$(s)$ regarding defects in solids is(are):
$A$. Frenkel defect is usually favoured by a very small difference in the sizes of cation and anion.
$B$. Frenkel defect is a dislocation defect.
$C$. Trapping of an electron in the lattice leads to the formation of $F$-center.
$D$. Schottky defects have no effect on the physical properties of solids.

At what temperature will the Schottky defect be maximum?

Assertion : Due to Frenkel defect,there is no effect on the density of the crystalline solid.
Reason : In Frenkel defect,no cation or anion leaves the crystal.

In an ionic solid,equal number of cations and anions are missing from their regular positions in the crystal lattice,creating vacancies. This is called-