☰
✕

The Solid State
Question
Wired Faculty App

Ionic solids, which have anionic vacancies due to metal excess defect, develop colour. Explain with the help of a suitale example.

Answer

When crystals of NaCl are heated in an atmosphre of sodium vapour, the sodium atoms are deposited on the surface of the crystal. The CI– ions diffuse to the surface of the crystal and combine with Na atoms to give NaCl. This happens by loss electron by sodium atom to form Na+ ions. The released electrons diffuse into the crystals and occupy anionic sites. As a result the crystal now has an excess of sodium. They impart yellow colour to the crystals of NaCl.

Sponsor Area

Some More Questions From The Solid State Chapter

Why do solids have a definite volume?

Classify the following as amorphous or crystalline solids: Polyurethane, naphthalene, benzoic acid, teflon, potassium nitrate, cellophane, polyvinyl chloride, fibre glass, copper.

Why is glass considred a super-cooled liquid?

Refractive index of a solid is observed to have the same value along all directions. Comment on the nature of this solid. Would it show clevage property?

Classify the following solids in different categories based on the nature of intermolecular forces operating in them:
Potassium sulphate, tin, benzene, urea, ammonia, water, zinc
sulphate, graphite, rubidium, argon, silicon carbide.

Solid A is a very hard, electrical insulator in solid as well as in molten state and melts at extremely high temperature. What type of solid is it?

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

What type of solids are electrical conductors, malleable and ductile?

Give the significance of a 'lattice point'.

Name the parameters that characterize a unit cell.