An ionic compound has a unit cell consisting of A ions at the corners of a cube and B ions on the centres of the faces. If side length is 10$A^{\large\circ}$, what is the density of the solid assuming atomic weights of A and B as 50 and 100 gms respectively.

Question

$\begin{array}{1 1} 1.082 \times 10^6 \; gm^{-3} \\5.812\; g\;cm^{-3} \\ 6.324 \times 10^6 \; gm^{-3} \\ 4.346 \; g\;cm^{-3} \end{array}$

Comments

How is z=1 here??
it must be 4