Which crystal does not have free electrons for electric conduction?
ionic crystal
covalent network crystal
both (a) and (b)
none of the above
Which covalent network crystal is an exception in electrical conductivity?
silicon carbide
diamond
graphite
none of these
At what temperature does the carbon atom in diamond splits?
40oC
4000oC
400oC
40000oC
Which unit cell have diamond cell?
triclinic
trigonal
octahedral
tetrahedral
____________ defect arise when an ions occupies an interestitial position between the lattice points.
Point defect
Schottky defect
Frenkel defect
Metal excess defect
W.L.Bragg and Wt Bragg derived a mathematical relation to determine interatomic distances from _____________ patterns.
X-ray diffraction
Wavelength
Interatomic distance
Crystal diffraction
An example of metal deficiency defect is .
NaCl
AgCl
CsCl
FeS
______________ defects appears generally in ionic crystal in which the positive and negative ions donot differ much in size.
Point
Frenkel
Schottky
Metal excess
Which of the following has 1.54 Ao bond length throughout the crystal?
sodium chloride
In the Bragg's equation for diffraction of x rays n' represents
The number or moles
Avagadro number
A quantum number
Order of reflection
