Solution:
ra = rc/0.225 = (79.55 pm)/0.225 =353.56 pm;
There are 4 molecules of M2X per unit cell of anti-fluorite structure. Hence
The compound M2O (molar mass= 200 g mol-1 ) has anti-fluorite closest unit cell. If the radius of M+ is 79.55 pm, the density of M2Owould be
ra = rc/0.225 = (79.55 pm)/0.225 =353.56 pm;
There are 4 molecules of M2X per unit cell of anti-fluorite structure. Hence