A crystal of lead (II) sulphide has NaCl strcuture . In this crystal the shorest distance between a `Pb^(2+)` ion and `S^(2-)` ion is 297 pm . What is the volume the of unit cell in lead sulphide ?

Answer

`a=5.94xx10^(-8)` cm, `V=a^3=2.096xx10^(-22) cm^3`

Explanation

Edge 'a' of unit cell = 2 x Distance between `Pb^(2+)` and `S^(2-)`ions .