Sodium oxide (na2o) crystallizes in a structure in which the o2– ions are in a face - centered cubic lattice and the na+ ions are in tetrahedral holes. what is the number of na+ ions in the unit cell? a)2 b)4 c)6 d)8 e)none of these

We have to know the number of Na⁺ ions in the unit cell.

The number of Na⁺ ions in the unit cell is (D) 8.

Sodium oxide (Na2O) crystallizes in a structure in which the O2– ions are in a face - centered cubic lattice and the Na+ ions are in tetrahedral holes.

O²⁻ ions are in a face centred cubic lattice, so the number of O²⁻ ions per unit cell is equal to 4. The number of  tetrahedral hole= 2 X 4=8. Na+ ions are present in tetrahedral holes, which indicates there are 8 number of Na+ ions in the unit cell.

answer; ///i do believe that the correct answer is (b); ///particle composed of two or more atoms bonded together;

1 a

2 d

3 a

4 c

explanation: