Question

If all the ions present along one of the rectangular plane of symmetry in NaCl structure are removed what will be the new formula of rock salt?
Please post the full answer. ​

Answer 1

Answer:

Explanation:

In rocksalt (NaCl) structure, Cl  

−

 ions forms fcc and Na  

+

 ions are present on the edge centre and body center.

Let, in the given compound AB, A forms fcc and B is present on the edge center and body center.

The effective number of atoms of A=4

The effective number of atoms of B=4

Now, if all atoms touching one body diagonals plane are removed except body center then, 4 atoms are removed from the corner and 2 atoms are removed from face centers and 2 are removed from edge centers.

So, Effective number of atoms of B left =4−  

2

2

​  

−  

4

2

​  

=2.5

Effective number of atoms of A left =4−  

8

4

​  

=3.5

So, the formula of unit cell is A  

3.5

​  

B  

2.5

​