For an ionic crystal with the general formula $AX$,the coordination number is $6$. What is the radius ratio range?

Potassium fluoride $(KF)$ has a $NaCl$ type structure. If the edge length of the unit cell is $a$,what is the distance between $K^+$ and $F^-$ ions?

Calculate the number of atoms per unit cell in a face-centered cubic $(fcc)$ unit cell.

The radius of the calcium ion is $94 \text{ pm}$ and the radius of the oxide ion is $146 \text{ pm}$. What is the possible crystal structure of calcium oxide?

What is the coordination number of a particle in $hcp$ structure?

In an alloy of metals $M$ and $N$,$N$ atoms form a $bcc$ structure,while $M$ atoms occupy the center of each face. If the cube is cut such that all atoms along one body diagonal are removed,the formula of the resulting solid will be ...........