Structure of a mixed oxide is cubic close packed (ccp). The cubic unit cell of mixed oxide is composed of oxide ions. One fourth of the tetrahedral voids are occupied by divalent metal A and the octahedral voids are occupied by a monovalent metal B . The formula of the oxide is

Step-by-step solution

According to ccp, Number of O ²⁻ ions =4 So, tetrahedral void =8 and octahedral void =4 Since, A ions occupied 1 4 th of tetrahedral void. Number of A ions = 1 4 8=2 Again, B ions occupied all octahedral void. Number of B ions =4 aligned A: B: O & =2: 4: 4 & =1: 2: 2 aligned Structure of oxide =A B₂ O ₂