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Which choice is an example of ionic solid?
NaCl
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Which statement about network solids is false?
Graphite is an example of a three-dimensional network solid.
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Which are properties of all metals?
I,II,III
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Which statment is false?
Molecular solids are held together by covalent bonds
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Elements most likely to be used for doping silicon in making semiconductors are
Ga, As, B
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A diatomic element is a shiny purple solid at room temperature that sublimes upon gentle heating. It is slightly soluble in water and considerably more soluble in alcohol. It does not conduct electricity as a solid, liquid or solution. This solid can best be classified as
Molecular
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Which statement is false?
None of these choices are false
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Which choice is an example of a metallic solid?
iron
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In an _____ semiconductor the charge carriers are the holes because _____.
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Ultrapure silicon for use in the semiconductor industry can be obtained by the process of
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According to band theory, a semiconductor is a material which has a(an) _____ valence band, a(an) _____ conduction band, and _____ between them.
partially filled; empty; a narrow gap
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Three classifications of ceramics include those made from clay, called _____ ceramics; those made of alumina and magnesia, called _____ ceramics; and those made of nitrides and carbides, called _____ ceramics.
silicate; oxide; nonoxide
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According to band theory, an insulator is a material which has a(an) _____ valence band, a(an) _____ conduction band, and a _____ gap between them.
partially filled; empty; wide
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Which statement about optical fibers is false?
Optical fibers are worse than copper wire in the transmission of voice data, such as telephone conversations, because the fibers have more interference.
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According to band theory, a good conductor is a material which has a(an) _____ valence band, a(an) _____ conduction band, and _____ between them.
partially filled; empty; no gap
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Viscosity
is the resistance to flow.
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Surface tension
is the energy that requires to form a flat surface.
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Capillary action
is the rise of liquid through small diameter tube without an external force.
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Meniscus
is the shape of the liquid surface when it is inside a small diameter tube.
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Volatility
is the tendency of a liquid to vaporize
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P = Vapor pressure
R = Universal gas constant = 8.31 Jmol-1K-1
= Molar enthalpy of vaporization vapH
C = Clausius–Clapeyron Constant
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Energy band
is a large group of orbitals whose energies are closely spaced and whose average energy is the same as the energy of the corresponding orbital in an individual atom.
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Valence band
is a band containing the valence electrons.
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Conduction band
contains high energy orbitals with an average energy above valance band.
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Conductor
has an excellent electrical conductivity.
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Insulators
do not conduct electricity.
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Superconductors
offer zero resistance to electric conductivity.
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Semiconductor
can act as either conductor or insulator depending on the external electric field.
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Composite
- -Materials combining from the other three categories.
- -Usually blend in a way that gives best of each component depending on the application.
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