Give any three characteristics of ionic crystals.

Explain briefly seven types of unit cell.

Distinguish between hexagonal close packing and cubic close packing.

Distinguish tetrahedral and octahedral voids.

Explain Schottky defect.

What is meant by the term “coordination number”? What is the coordination number of atoms in a bcc structure?

An element has bcc structure with a cell edge 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.

Aluminium crystallizes in a cubic close packed structure. Its metallic radius is 125pm. calculate the edge length of unit cell.

If NaCl is doped with 10^-2 mol percentage of strontium chloride, what is the concentration of  cation vacancy?

Atoms X and Y form bcc crystalline structure. Atom X is present at the corners of the cube and Y is at the centre of the cube. What is the formula of the compound?

Sodium metal crystallizes in bcc structure with the edge length of the unit cell 4.3 x 10^-8 cm. Calculate the radius of sodium atom.

Write a note on Frenkel defect.

Barium has a body centered cubic unit cell with a length of 508pm along an edge. What is the density of barium in g cm^-3?