Solid State

In a cubic unit cell of an ionic compound, the eight corners are occupied by anions and cations at the center of the cube. Calculate the volume of the unit cell if density of the unit cell is $4 \text{ g cm}^{-3}$.
[Molar mass of compound $= 168.6$ g mol$^{-1}$ and $N_A = 6.022 \times 10^{23}$]