A mineral having the formula `XY_(2)` crystaillises in the cubic closed packed lattic with the A- atoms occupaying the lattice point .Fraction of the betradral sites occupired by B- atoms is

Options

A. `1.00`
B. `0.52`
C. `0.68`
D. `0.74`

Answer

A

Explanation

`AB_(2)` cryswtanllises as cubic packed (ccp)
This `A^(2+)` is surrounded by edge `B^(-)`
and `B` is surrounding by four `A^(2 +)`
Thus coordination number of `A^(2+) = 8`
Coordination number of `B^(-) = 4`
Number of atoms as trtahoudral in small of unit of atoms `B= 4`
Thus fraction occepaid `= (4)/(4) = 1 (100%)`