________________ is the property of a material by which it allows the flow if electric current.
Resistivity
Conductivity
Superconductivity
Sublimation
_______________ is the smallest fundamental repeating portion of a crystal lattice from which the crystal is built by repetition in three dimension.
Unit cell
Void
Ionic crystal
Covalent crystal
An example of metal excess defects is
Agcl
Nacl
Cscl
Fes
The force that binds a metal ion to a number of electrons within its sphere of influence is known as
Covalent bond
Ionic bond
Coordinate bond
Metallic bond
If the deviation occurs due to missing atoms, displaced atoms or extra atoms, the imperfection is named as
Schottry defect
Point defect
Frenkel defect
Metal excess defect
At what temperature does the carbon atom in diamond splits?
40oC
4000oC
400oC
40000oC
Which of the following is extremely hard?
coal
silicon carbide
coke
plastic
Which crystal does not have free electrons for electric conduction?
ionic crystal
covalent network crystal
both (a) and (b)
none of the above
Which of the following allows light to pass through it?
diamond
lead
graphite
Which unit cell have diamond cell?
triclinic
trigonal
octahedral
tetrahedral
