The ratio of the effective number of atoms in a unit cell of $fcc$ and $bcc$ lattices is

The number of octahedral voids in a $BCC$ structure is:

Explain the crystal structure of sodium chloride $(NaCl)$.

$A$ compound is formed by elements $A$ and $B$. This crystallises in the cubic structure where the $A$ atoms are at the corners of the cube and $B$ atoms are at the body centres. The simplest formula of the compound is

An element has a $bcc$ structure with $12.08 \times 10^{23}$ unit cells. What is the total number of atoms in these unit cells?

The number of spheres contained $(i)$ in one body centred cubic unit cell and $(ii)$ in one face centred cubic unit cell,is