Show the variance of electrical conductivity of semiconductors with temperature graphicallly
What is ratio of co-ordination numbers is AB2 and A2B type structure.
How many atoms are present in the unit cell of
(i) Simple cubic
What is radius ration? Discuss its significance very briefly
Defferentiate unit cell and space lattice?
Which type of semiconductor will you obtain by addition phosphorous to the pure crystal of silicon
What is schottky defect?
What is the radius ratio found in sodium chloride and cesium chloride structures
A compound formed by elements A and B has a cubic structure in which A atoms are at the corners of the cube and B atoms are at the face centers. Predict the formulae of the compound.
If radius ratio be 0.414 what will be the co-ordination no. & structural arrangement?
Xenon crystallizes in the FCC lattice and the edge of the unit cell is 620 pm what is the nearest neighbor distance and What is the radius of the Xenon atom What is the relationship between the radius and edge length in BCC structure.
Differentiate Schottky defect and Frankel defect. Name the compound which exhibits both.
Illustrate metal excess defect. Why the NaCl crystal acquires yellow colour when the sodium vapor is passed over it?
Write four difference between crystalline and amorphous solids.
Write a short note on ‘superconductivity’?
What is doping? Explain with the help of an example?
Defive the expression extablishing the relationship between ratius and edge length in a body centred cubic structure.
Explain Bragg’s equation by deriving it.
Write the differences between paramagnetic and diamagnetic substances?
Why is Frenkel defect not found in pure alkali metal halides?
Explain the following: i. Piezoelectricity ii. Pyroelectricity iii. Ferroelectricity.
Explain sodium chloride structure with the help of a neat diagram
What are amorphous solids ? Explain with the properties.
What are primitive unit cells? Write the name of all seven unit cells in crystals
Derive the packing efficiency in body centered cubic structure. How will you define the packing fraction?
Explain Ferromagnetic, antiferromagnetic and ferromagnetic substances.
i. Cesium chloride is more stable than sodium chloride why
ii. Why Si doped in P is super conductor
iii. The electrical conductivity of a metal decreases with rise in temperature
An element has a BCC structure with a cell edge of 288 pm. The density of the element is 7.2 gm/cc. How many atoms are present in 208 gm. Of the element.
Explain Tetrahedral and octahedral voids. How many tetrahedral voids are there found in ccp structure?
The density of Cr is 7.2 gm/cc if the unit cell is cubic with edge length 289 pm, determine the type of the unit cell ( atomic mass 52 amu)
Explain the rock salt structure of Ionic compound. How does it differ from cesium chloride structure.
i. What is F center defect.
ii. What is understood by forbidden zone
iii. The conductivity of insulators, semiconductors and conductors on the basis of band theory
i. Explain all the electrical properties of solid
ii. What is an electron vacancy or hole
iii. What are interstitials.
i. Defferentiate hcp and ccp
ii. Illustrate the CsCl structure.