Define unit cell.

Give any three characteristics of ionic crystals.

Differentiate crystalline solids and amorphous solids.

Classify the following solids
a. P₄
b. Brass
c. diamond
d. NaCl
e. Iodine

Explain briefly seven types of unit cell.

Distinguish between hexagonal close packing and cubic close packing.

Distinguish tetrahedral and octahedral voids.

What are point defects?

What type of stoichiometric defect is shown by ZnS.

Ionic solids conduct electricity in molten state but not in solid state. Explain.

Define void.

What is point defect in crystals?

A compound made up of two atoms X and Y has a face centred cubic arrangement. X is present in the coners and Y at the centre of each face. If one atom is missing from comer. What is the simplest formula of the compound.

Name the seven primitive crystal systems.

The energy required to vapourize one mole of copper is smaller than that of energy required to vapourise 1 mole of diamond why?