__________ is the regular three dimensional arrangement of particles in a crystal.
a crystal
a crystal lattice
a unit cell
a solid state
in ______ crystals the lattice sites are occupied by single atom, each of which is covalently bonded to its neighboring atoms.
Ionic crystals
Covalent network crystals
Metallic crystals
Covalent molecular crystals
On Which crystal a beam of light excites its mobile electrons?
Atomic crystal
Molecular crystal
Metallic crystal
Ionic crystal
What is the C-C bond length in diamond?
1.31 Ao
2.6 Ao
1.54 Ao
0.86 Ao
Which of the following is extremely hard?
coal
silicon carbide
coke
plastic
In _______ cubic unit cell, there is a structural particles within the body of the cell means the center of the cube.
Primitive
Face centered
Body centered
End centered
What gets excited when a beam of light is incident on the surface of a metal?
Positive ions
Mobile electrons
Negative ions
Mobile protons
How many carbon atoms are surrounded in diamond structure?
8
2
4
6
Which of the following are held together by both dispersion forces and dipole- dipole forces?
semi polar molecules
polar molecules
quiater polar molecules
non polar molecules
The co-ordination number of face centered cubic unit cell is
10
12
14
