In a face centred cubic arrangement of A and B atoms in which ‘A’ atoms are at the corners of the unit cell and .B. atoms are at the face centers, one of the ‘A’ atoms is missing from one corner in the unit cell. The simplest formula of the compound is

Options

A. `AB_(3)`
B. `A_(7)B_(24)`
C. `A_(7)B_(8)`
D. `A_(7)B_(8)`

Answer

B

Explanation

Number of A atoms at the corners = `7 xx (1)/(8)= (7)/(8)`
No. of B atoms at face centres = `6 xx (1)/(2) = 3`
Ratio of `A: B = (7)/(8) : 3 = 7:24`
`:.` Formula of compound is `A_(7)B_(24)`