+91-8076753736 [email protected]

-->

The Solid State

Question

Wired Faculty App

An element a crystallises in fcc structure. 200 g of this element has 4.12 x 10²⁴atoms. The density of A is 7.2 g cm^-3. Calculate the edge length of the unit cell?

Solution

solution:
we have given that
mass = 200g
density = 7.2 g cm^-3
N_A = 4.12 x 10²⁴
Z = 4
by using the following equation,

ρ = \frac{z \times M}{a^{3} \times N_{A}}

\Rightarrow

a^{3} = \frac{Z \times M}{d \times N}

= \frac{4 \times 200}{7.2 \times 4.12 \times 10^{24}} = \frac{800}{29.664} \times 10^{- 24}

a^{3} = 26.968 \times 10^{- 24} a = 2.997 \times 10^{- 8} a = 299.7 pm .

hence the edge length is 299.7pm

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.

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation