In a face centred cubic lattice, atom `A` occupies the corner positions and atom `B` occupies the face centred positions. If one atom of `B` is missin from one of the face centred points,, the formula of the compound is `:`

Options

A. `AB_(2)`
B. `A_(2)B_(3)`
C. `A_(2)B_(5)`
D. `A_(1)B`

Answer

C

Explanation

Effective no. of A atoms `=(1)/(8) xx8=1`
Effective no. of B atoms `=(1)/(2) xx 5` (one is missing) `=(5)/(2)`
Therefore formula is `A_(1)B_(5//2)=A_(2)B_(5)`