Fri March 04, 2011 By: Dipti Priya

In a solid having FCC structure oxide ions constitutes lattice points of the solid if divalent cation (A2+) occupys 25% of octahedral void and trivalent cation (B3+) occupy 12.5% of the tetrahedral void ,then what is the formula of solid?

Expert Reply
Sat March 05, 2011
Lattice points=No. of atoms in crystal
No. of Octahedral void =No. of lattice sites
No. of tetrahedral voids= 2. No. of lattice sites
Let us consider The lattice sites (O-2)=x
No. of octaherdal Voids (A+2)=x.25/100
No. of tetrahedral Voids (B+3)=2x.12.5/100
x: x.25/100: 2x.12.5/100
Hence the formulais
Home Work Help