Question

On increasing pressure the coordination number of $NaCl$ type structure changes from:

• A. $6:4\text{to}6:6$
• B. $6:8\text{to}8:6$
• C. $6:6\text{to}8:8$
• D. $8:6\text{to}6:6$

Answer 1

The correct option is C $6:6\text{to}8:8$

Temperature and pressure plays an important role in crystal structure of the compound.
On increasing the temperature, the coordination number of constituents in compound tends to decrease.
On increasing the pressure, the coordination number tends to increase.
The coordination number of 6:6 of $NaCl$ type can be coverted to coordination number of 8:8 of $CsCl$ type by applying high pressure.