$A$ compound made of elements $A$ and $B$ forms an $fcc$ structure. Atoms of $A$ are at the corners and atoms of $B$ are present at the centres of the faces of the cube. What is the formula of the compound?

If the number of atoms per unit cell in a crystal is $2$,the structure of the crystal is:

If all ions touching an axis passing through two opposite face-centres of unit cell are removed in $NaCl$ (rock salt) structure in which $Cl^{-}$ ions form $CCP$ and $Na^{+}$ ions occupy all octahedral voids,then the effective number of $Cl^{-}$ ions per unit cell is:

Which statement is not correct?

In the calcium fluoride structure,the coordination number of the cation and anion are respectively:

The solid $AB$ has a $NaCl$ type structure. If the radius of the $A^{+}$ ion is $120 \, pm$, then the maximum radius of the $B^{-}$ ion will be ........... $pm$.