☰
✕

The Solid State
Question
Wired Faculty App

The edge length of a face centred cubic cell of an ionic substance is 508 pm. If the radius of the cation is 110 pm, the radius of the anion is 

  • 144 pm

  • 288 pm

  • 398 pm

  • 618 pm

Answer

A.

144 pm

For FCC lattice (assuming cation in octahedral void and anion in FCC)
a = 508 pm
(r+ + r-) = a/2 = 508/2 = 254 pm
(r+ + r-) = 254 pm
r- = 254-110 = 144 pm

Sponsor Area

Some More Questions From The Solid State Chapter

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.

Distinguish between Hexagonal and monoclinic unit cells.

Distinguish between Face-centred and end-centred unit cells.