Q: Select the correct statement(s)
(A) The C.N. of cation occupying a tetrahedral hole is 4
(B) The C.N. of cation occupying a octahedral hole is 6
(C) In Schotky defects, density of the lattice decreases.
(D) In Frenkel defects, density of the lattice increases.
Solution: Since tetrahedral holes are surrounded by 4 nearest neighbours. So, the C.N. of cation occupying tetrahedral hole is 4. Since octahedral hole is surrounded by six nearest neighbours, so, C.N. of cation occupying octahedral is 6.
In schottky a pair of anion and cation leaves the lattice, so density of lattice decreases.
Ans: (A), (B), (C)