20 questions
The number of nearest particles which is in direct contact with a particle in a closed packed structure
Unit Cell
Void
Packing efficiency
Coordination number
Crystal system characterized by a ≠ b≠ c and α = β = γ = 90o
Hexagonal
Ortho rhombic
Tetragonal
Triclinic
Smallest repeating unit of crystal lattice
Lattice site
Unit cell
Crystal lattice
Lattice point
In a primitive unit cell atoms are present at the
Corners & Centers of any 2 opposite sides
Corners only
Corners and Body Centre
Corners & Centers of all faces
There are ……….. Bravais lattices corresponding to 7 different Crystal Systems
8
9
14
13
Number of atoms per unit cell in a Face Centered Cubic lattice
4
1
2
6
The wrong statement about Para magnetism
They are weakly attracted by a magnetic field
They are magnetized in a magnetic field in the same direction
They keep their magnetism in the absence of magnetic field
It is due to the presence of one or more unpaired electrons
Example for crystalline solid
Glass
Quartz
Plastic
Rubber
Crystalline solids are
Isotropic
Allotropic
Anisotropic
Isomorphic
Crystal showing both Schottky & Frenkel defect
AgBr
ZnO
AgI
NaCl
Defect shown by ionic crystals with large difference in size
Schottky Defect
Impurity Defect
Frenkel Defect
Metal Deficiency Defect
Anionic sites occupied by unpaired electrons are called
F Centres
Interstitial Centres
Cationic Centres
Anionic Centres
Frenkel defect is also known as
Metal Deficiency Defect
Impurity Defect
Metal Excess Defect
Dislocation Defect
p-type semiconductors are formed when Silicon or Germanium is doped with Group
13
14
12
15
An amorphous solid
CaCl2
NaCl
Glass
CsCl
Defect causing decrease in density
Schottky
Frenkel
F- centre
Metal Excess
A semiconductor material
Ga
As
Ge
Al
An example for Network solid
Corundum
Diamond
Dry Ice
KCl
Density of a crystal is given by the formula
AB AB … type close packing pattern represents
HCP
FCC
CCP
BCC