What is the coordination number of $Cs^{+}$ and $Cl^{-}$ ions in the $CsCl$ structure?

An ionic compound is expected to have a tetrahedral structure if the radius ratio $r_{+} / r_{-}$ lies in the range of:

The number of unit cells in $58.5 \ g$ of $NaCl$ is nearly

The ratio of cationic radius to anionic radius in an ionic crystal is greater than $0.732$. Its coordination number is

$A$ compound contains $Ca, Ti$ and $O$ elements. If $Ca^{2+}$ ions are at the corners of the cube,$Ti$ ions are at the body center,and $O^{2-}$ ions are at the face centers,then the molecular formula of the compound and the oxidation state of $Ti$ are respectively ........

$A$ compound having elements $X$ and $Y$ crystallises in a cubic structure, where $X$ is at the corner position and $Y$ is at the center of the cube. The correct formula of the compound is