AP EAPCET 25-Aug-2021 Shift 1 Paper

According to mixed oxide, number of O2− ions =4
So, number of tetrahedral voids =8
and number of octahedral voids =4
B occupies

2

3

rd of tetrahedral void =8×

2

3

=

16

3

A occupies all octahedral voids =4
Now, A:B:O
4:

16

3

:4
⇒ 12:16:12
⇒ 3:4:3 (in simplest ratio)
Hence, molecular formula of this oxide is A3B4O3.