Question

Select the correct statement(s):-
i)Schottky defect is shown by CsCl
ii)Frenkel defect is shown by Zns
iii)Hexagonal close packing (hcp) & Cubic close packing (ccp) structure has same co-ordination no.12

iv) At high pressure, the co-ordination number increases.

• A. i, ii, iii & iv
• B. i, ii, & iv
• C. ii, iii & iv
• D. i, iii& iv

Answer 1

The correct option is A

i, ii, iii & iv

Schottky defect is shown by crystals having higher value of limiting radius ratio (higher coordination number) = 8 in CsCl
Frenkel defect is shown by crystals having lower value of limiting radius ratio (lower coordination number)= 4 in ZnS

Hexagonal close packing (hcp) & Cubic close packing (ccp) structure has same packing fraction