Question

If the pressure on $NaCl$ structure is increased, then its coordination number will:

• A. increase
• B. decrease
• C. either $\left(A\right)$ or $\left(B\right)$
• D. remain the same

Answer 1

The correct option is A increase

If the pressure on a $NaCl$ structure is increased, then its coordination number will increase.

$NaCl$ crystal has 6:6 coordination number. When pressure is applied, ions come closer to each other. This gives close packed (more compact) structure. The coordination number increases to 8:8 and the structure changes to $CsCl$ type structure.