Solid State Question 287
Question: Which set of following characteristics for $ ZnS $ crystal is correct-
Options:
A) Coordination number (4 :4); $ ccp;Z{{n}^{2+}} $ ion in the alternate tetrahedral voids.
B) Coordination number (6 : 6); $ hcp;\ Z{{n}^{2+}} $ ion in all tetrahedral voids.
C) Coordination number (6 :4); $ hcp;Z{{n}^{2+}} $ ion in all octahedral voids.
D) Coordination number (4:4); $ ccp;Z{{n}^{2+}} $ ion in all tetrahedral voids.
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ ZnS $ has cubic close packed (ccp) structure. The $ {{S}^{2-}} $ ions are present at the corners of the cube and at the centre of each face. Zinc ions occupy half of the tetrahedral sites. Each zinc ion is surrounded by four sulphide ions which are disposed towards the comers of a regular tetrahedron. Similarly, $ {{S}^{2-}} $ ion is surrounded by four $ Z{{n}^{2+}} $ ions.
BETA
