If the radii of `Mg^(2+), Cs^(o+), O^(2-), S^(2-)`, and `CI^(Θ)` ions are `0.65, 1.69, 1.40, 1.84`, and `1.81 Å`, respectively, calculate the coordination number of the cation in the crystals of `MgS, MgO`, and `C_(s)CI`.

Explanation

for Mgs `(r_(+))/(r_(-))`=0.353
coordination no=4
tetrahedral void
`MgOimplies (r_(+))/(r_(-))=(0.65)/(1.40)=0.464`
Octahedral voids
coordination no. = 6
CsCl`=(r_(+))/(r_(-))=(1.69)/(1.81)`=0.934
BCC coordination no. =8