SOLID STATE

Which type of defect has the presence of cations in the interstitial site?

• Schottky defect

• Frenkel defect

• Metal deficiency defect

• Vacancy defect

In which pair the most efficient packing is present?

• hcp and bcc

• hcp and ccp

• bcc and ccp

• bcc and scc

Which of the following point defects are shown by AgBr(s) crystals.

• Schottky defect

• Frenkel defects

• Both Schottky and Frenkel

• Metal excess defect

The percentage of empty space in a body centred cubic arrangement is............

• 74

• 68

• 26

• 32

The total number of tetrahedral voids in the face centred unit cell is............

• 6

• 8

• 10

• 12

Which of the following defects is also known as dislocation defect?

• Frenkel defect

• Schottky defect

• Non- stoichiometric defect

• Simple interstitial defect.

What is the coordination number in a square closed packed structure in two dimensions.

• 2

• 3

• 4

• 6

A compound is formed by two elements X and Y. Atoms of the element Y (as anions) make ccp and those of the element X (as cations) occupy all the octahedral voids. The formula of the compound is

• X ₂Y

• X ₄Y

• XY₂

• XY

The coordination number in hcp is

• 6

• 12

• 18

• 24

The space lattice of graphite is

• Cubic

• Tetragonal

• Rhombic

• Hexagonal