Question

A unit cell consist of a cube in which anions B are present at each corner and cations A at the centre of the alternative faces of the unit cell. What is the simplest formula of the compound?

Answer 1

B=8*1/8=1
and A=3*1/2
3 because they are at alternate faces and contribution of each is 1/2
So simplest formula is 
A₃B₂


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