Question

The structure of $N{a}_{2}O$ crystal is:

• A. $CsCl$ type
• B. $NaCl$ type
• C. $KCl$ type
• D. anti-fluorite

Answer 1

Answer: (D)

anti-fluorite

Sodium oxide had got anti fluorite structure. Since Sodium ions are smaller in size they go to voids and since the number of sodium ions is twice the number of oxide ions, all the tetrahedral voids are filled. So the structure comes out as oxide ions are at face and corners of cube to form a fcc lattice and sodium ions occupy all the tetrahedral voids .