What is the total number of atoms in a $BCC$ crystal lattice having $1.8 \times 10^{20}$ unit cells?

The $FCC$ crystal contains how many atoms in each unit cell?

$KBr$ crystallizes in a $fcc$ lattice (similar to $NaCl$). The second nearest neighbor of $K^+$ ion and its number are:

An element has a body-centered cubic $(BCC)$ structure with an edge length of $288 \ pm$. The density of the element is $7.2 \ g/cm^3$. How many atoms are present in $208 \ g$ of the element?

How many "nearest" and "next nearest" neighbours,respectively,does potassium have in a $bcc$ lattice?

$A$ crystal is formed by two elements $X$ and $Y$ in a cubic structure. $X$ atoms are at the corners of a cube,while $Y$ atoms are at the face centers. The formula of the compound will be: