1) The molecules of the substance are formed by polar covalent bonds:
A) HCL.
B) H2.
C) CL2.
D) I2.
2) There are only 14 possible 3D lattices are called:
A) Straight lattice.
B) Unit lattice.
C) Bravais lattice.
D) Crystal lattice.
3) Packing efficiency of hcp:
A) 74.
B) 70.
C) 72.
D) 80.
4)The point defect that does not disturbs the stoichiometric of the solid.
A. Intrinsic defect.
B. Thermodynamic defect.
C. Both a & b.
D. None.
5) When some of the lattice sides are vacant, the crystal is said to have vacancy defect.
A. Density is decreased.
B. Density is increased.
C. Density is constant.
D. None.
6) Vacancy defect shows:
A. Frenkel defect.
B. Schottky defect.
C. Dissolocation defect.
D. Interstitial defect.
7) Metal excess defect due to:
A. Anionic defect.
B. Cationic defect.
C. Intermolecular defect.
D. Both a & b.
8) The metals which allow passage of electricity is called:
A. Conductors
B. Insulators
C. Semiconductors
D. None
9) The substance that is weakly attracted by a magnetic field:
A. Antiferro.
B. Paramagnetism.
C. Diamagnetism.
D. Ferromagnetism.
10) A few substances like iron, cobalt, nickel are attracted very strongly by a magnetic field.
A. Paramagnet.
B. Ferromagnet.
C. Diamagnet.
D. Antiferro.
11) Simple cubic has:
A. 3 atoms.
B. 2 atoms.
C. 1 atom.
D. 4 atoms.
12) FCC has:
A. 1 atom
B. 4 atoms
C. 3 atoms
D. 2 atoms
13) Crystalline solid has:
A. Long-term order.
B. Short-term order.
C. Maximum order.
D. Minimum order.
14) Group 13-15 elements contain:
A. N-type semiconductor.
B. P-type semiconductor.
C. Both a & b.
D. Neutral semiconductor.
15) The impurities are introduced by semiconductor that changed their electrical properties:
A. Doping.
B. Hopping.
C. Electrical conductors.
D. Sea of electrons.
16) The example of amphorous & crystalline solid:
A. Quartz.
B. Sea of electrons.
C. Diamond.
D. Graphite.
17) Bcc has:
A. 2 atoms.
B. 4 atoms.
C. 1 atom.
D. 3 atoms.
18)the regular 3d arrangement of points in a space:
A. Point lattice
B.crystal lattice
C.bravis lattice
D primitive lattice
19) The anionic sites occupied by unpaired electrons are called:
A. F center.
B. C center.
C. B center.
D. Both a & b.
20) Semiconductors of solid with conductivity in the internet range from:
A. 10^-6 to 10^ 4.
B. 10^-20 to 10^-10.
C. 10^7.
D. 10^-20 to 10^6.