Chemistry - Solid State Question with Solution | TestHub
How many of the following statements are correct?
(1) In CCP distance between two nearest octahedral voids is
(2) In CCP distance between nearest tethrahedral and octahedral voids is
(3) In CCP distance between two nearest voids is
(4) In CCP distance between next nearest tetrahedral void and farthest octahedral voids is
(5) In HCP along every edge, centres of two tetrahedral voids and one octahedral void is located
(6) In HCP, if a plane is passed parallel to top face but at , from bottom it pass through centres of octahedral voids. (h is the height of ionsmatic unit cell)
(7) In HCP, top plane pass through centres of both tetrahedral and octahedral voids.
Answer:
Solution:
In CCP (FCC) structure, the positions of octahedral and tetrahedral voids follow fixed geometric rules.
(1) In CCP, distance between two nearest octahedral voids is 2R, so it is correct.
(3) In CCP, distance between nearest voids is √2 R, so it is also correct.
Statements (2), (4), (5), (6), and (7) do not match standard geometrical relations of close packing, so they are incorrect.
Therefore, only 2 statements are correct.