Question

35. In NaCl structure, CH- form the C.C.P. lattice Which of the following change in NaCl structure occur so that formula become Na3Cl (Ignore electrical neutrality)? (1) If particles along one body diagonal are removed (2) If particles along two fourfold axis are removed (3) Particle along one face diagonal plane is removed (4) If particles along one fourfold axis are removed​

Answer 1

Answer:

Correct option is

A

Na

7

Cl

8

In NaCl structure Na

+

ion will occupy the tetrahedral voids while the Cl

−

ion will occupy the FCC lattice

At the corners =

2

1

×6=3

And at the octahedral body diagonal =1

Total number of octahedral voids in FCC lattice is =4

Thus, if the Na

+

ion is lost from one of the corner then the total number of Na

+

ion =

2

1

(6−1)+1=

2

7

And Number of Cl

−

ions =4

Therefore the formula is Na

7

Cl

8