Solid State Question 42
Question: Predict coordination number of the cation in crystals of the following compounds:
- $ MgO:r _{c}=0.65\overset{o}{\mathop{A}};r _{a}=1.40\overset{o}{\mathop{A}}, $
- $ MgS:r _{c}=0.65\overset{o}{\mathop{A}};r _{a}=1.84\overset{o}{\mathop{A}}, $
Options:
A) 6, 4
B) 4, 6
C) 3, 4
D) 6, 8
Show Answer
Answer:
Correct Answer: A
Solution:
[a] For $ MgO,=\frac{r _{c}}{r _{d}}=\frac{0.65}{1.4}=0.47 $
$ M{{g}^{2+}} $ is in octahedral void so C.N. = 6 For $ MgS,\frac{r _{c}}{r _{a}}=\frac{0.65}{1.84}=0.353 $
$ M{{g}^{2+}} $ is in tetrahedral void so C.N. = 4
BETA
