In a face-centered cubic lattice,a unit cell is shared equally by how many unit cells?

$A$ crystal is made up of metal ions $M_1$ and $M_2$ and oxide ions. Oxide ions form a $ccp$ lattice structure. The cation $M_1$ occupies $50 \%$ of octahedral voids and the cation $M_2$ occupies $12.5 \%$ of tetrahedral voids of the oxide lattice. The oxidation numbers of $M_1$ and $M_2$ are,respectively:

$CsCl$ crystallises in a body-centred cubic $(BCC)$ lattice. If '$a$' is its edge length,then which of the following expressions is correct?

If a metal has a $fcc$ crystal structure,the coordination number is $12$ because

$A$ solid compound contains atoms $X, Y,$ and $Z$. In its unit cell,atoms $X$ are at the corners,atoms $Y$ are at the body center,and atoms $Z$ are at the face centers. The formula of the compound is:

For $bcc$ cubic coordination the value of radius ratio is