In a solid ,oxide `(O^(2-))` ions are arranged in ccp, cations `(A^(3+))` occupy one -sixth of tetrahedral void and cations `(B^(3+))` occupy one -third of the octahedral voids . What is the formula of the compound?

Explanation

To find the formula of the compound based on the arrangement of oxide ions and the occupation of cation voids, we can follow these steps:

### Step 1: Determine the number of oxide ions (O²⁻) in the unit cell.
In a face-centered cubic (FCC) structure, the number of atoms (or ions) per unit cell is 4. Since the oxide ions are arranged in a CCP (cubic close-packed) structure, we have:
- Number of O²⁻ ions = 4

### Step 2: Calculate the number of tetrahedral voids.
In an FCC structure, the number of tetrahedral voids is given by:
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