Question

In NaCl structure, which one of the following
operations will change the formula of NaCl?
a.Removal of all ions present at one of the
body diagonal plane
b.Removal of all ions present at one of C3-axis
of symmetry
c.Removal of all ions present at one of
rectangular plane of symmetry
d.Removal of all ions present at one of C4-axis
of symmetry​

Answer 1

a.Removal of all ions present at one of the body diagonal plane.

Explanation:

In NaCl structure, removal of all ions present at one of the body diagonal planes will change the formula of NaCl.

• Removal of all atoms along body diagonal plane means removal of 4 corners, 1 body centre, 2 edge centres and 2 face centres.
• So 1 Na+ ions will be removed from body centre and 2 from edge centres.
• Cl− ions will be removed from corners and 2 from face centres.

Option A is the answer.