Question

The spinal structure (AB2O4) consists of an fcc array of O2– ions in which the :

• A. A cation occupies one-eighth of the tetrahedral holes and B cation occupies one-half of octahedral holes
• B. A cation occupies one-fourth of the tetrahedral holes and the B cations the octahedral holes
• C. A cation occupies one-eighth of the octahedral hole and the B cation the tetrahedral holes
• D. A cation occupies one-fourth of the octahedral holes and the B cations the tetrahedral holes

Answer 1

Answer: (A)

A cation occupies one-eighth of the tetrahedral holes and B cation occupies one-half of octahedral holes

Answer 2

A $\rightarrow$ $\frac{1}{8}$× 8 = 1, B $\rightarrow$ 4 ´ $\frac{1}{2}$= 2 and O2– = 4 so formula of spinal = AB2O4