Solid State Question 255
Question: A mineral has molecular formula $ XY_2O_4\cdot {{O}^{2-}} $ ions are arranged in ccp and cations of X are present in octahedral voids. Cations of Y are equally distributed among octahedral and tetrahedral voids. The fraction of the octahedral voids occupied will be
Options:
A) $ \frac{1}{6} $
B) $ \frac{1}{8} $
C) $ \frac{1}{4} $
D) $ \frac{1}{2} $
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Answer:
Correct Answer: D
Solution:
[d] Number of $ {{O}^{2-}} $ ions=n Number of tetrahedral voids=2n Number of octahedral voids=n Number of Y ions $ =\frac{n}{2} $ , Number of X ions $ =\frac{n}{4} $ Since Y ions are equally distributed among distributed among OVs and TVs. Occupied of octahedral voids $ =\frac{n}{4}+\frac{n}{4}=\frac{n}{2} $
$ \therefore $ Fraction of occupied octahedral void $ =\frac{n/2}{n}=\frac{1}{2} $
BETA
