Which type of solid is graphite?
planar network solid
ionic solid
metallic solid
none of these
Which of the following is held together by dispersion and dipole- dipole forces?
O2
I2
H2
CO2
The constituent particles in an ionic crystals are held together by powerful
Van Der Waal's forces
Chemical bonding
Electrostatic attraction
Molecular forces
Where does the metallic crystals have the Identical positive ions?
faces
points
sides
body centre
The number of nearest neighbors of an atom in a crystal lattice is called the
Rank of the unit cell
Crystal co-ordination number
Order of the unit cell
Dimensional number
Which of the following consist of molecular sheets?
diamond
graphite
sodium chloride
silicon carbide
At high temperature ___________ begin to oscillate in metallic crystals.
negative ions
protons
mobile electrons
positive ions
In which crystal light is reflected from the surface?
Metallic crystal
Ionic crystal
Atomic crystal
Molecular crystal
The co-ordination number of simple cubic unit cell is
2
4
6
8
Certain properties of a crystal such as refractive index, thermal and electrical conductivities etc are uniform in all directions. This phenomenon is known as
isopoly
isotropy
anisotropy
allotropy
