the ability of a material to conduct electricity is known as ____
electrical conductivity
conductance
Conductors, semiconductors, and insulators
electrical conductivity/ conductance in what unit of measurement?
siemens per meter (S/m)
Conductors, semiconductors, and insulators
if a material has a high level of conductance it is classified as a
_____
conductor
Conductors, semiconductors, and insulators
if a material has a low level of conductance it is classified as a
_____
insulator
Conductors, semiconductors, and insulators
what are the three main factors that determine the conductance of an element?
electron configuration
electronegativity
ionization energy
Electron Flow
the uniform movoment of electrons in a specific direction thru a conductor is known as _____
electric current
Electron Flow
current flows from _____ to _____
negative to positive
Electron Flow
what causes free electrons?
applied electrical force
Electron Flow
electrical flow occurs when a free electron leave on atom and goes to another
T/F
True
Electron Flow
what is an atom with more protons than electrons called?
positive ion
Electron Flow
what does a positive ion seek to balance its self out?
an electron
Electron Flow
what is an atom with more electrons than protons called?
negative ion
Electron Configuration
how are electron shells labelled?
K,L,M,N,O,P,Q
Electron Configuration
how many electrons can shell K hold?
2
Electron Configuration
how many electrons can shell L hold?
8
Electron Configuration
how many electrons can shell M hold?
18
Electron Configuration
all atoms must have full shells
T/F
False
Electron Configuration
if a atom has 8 electrons in the valence shell, the atom is considered to be
Stable/Unstable
stable
Electron Configuration
T/F
the 2nd outermost shell is not a factor when determining conductance
False
good conductors will have this shell full
Electron Configuration
which atoms have least chance of becoming free electrons
A. atom with 2nd most outer shell full
B. atom with 2nd most outer shell not full
B. bec the electrons in the valence shell have more forces pulling it into the 2nd outer most shell, making it hard for the electrons to become free electrons
Electronegativity and ionization energy
what is electronegativity
tendancy of an atom to attact electrons toward ifself
Measured using the pauling scale 0.7- 3.98
Electronegativity and ionization energy
what happens when electronegativity is low?
the atom would rather give off an electron than to keep it
Electronegativity and ionization energy
what happens when electronegativity is high
the atom wants to gain an electron
Electronegativity and ionization energy
what is ionization energy
the minimum amount of energy required to remove an electron from the valence shell
Measured in electron volts (eV)
Electronegativity and ionization energy
T/F
Higher values in Electronegativity and ionization makes for conductor
False
lower values in those to factors make for a better conductor
Types Of Materials
conductive materials allow ____ _____ to move thru it easily
free electrons
the more electrons that can move thru the material the better conductor it is
Types Of Materials
a Good conductor is a material that offers _____ ______ to electron movement
small opposition
they have low ionization energy
Types Of Materials
not all metals are good conductors
T/F
false
Types Of Materials
what three metals are the best conductors?
copper, gold, silver
Types Of Materials
why are copper, gold, and silver the best metal conductors?
bec they have full 2 outer most shell and one valence electron
and have low electronegativity and ionization energy
Types Of Materials
a material with properties of both conductors and insulators is called a _____
semiconductor
Types Of Materials
semiconductors act like an _____ but can conduct electricity if the electric force is strong enough to start the movement of free electrons
insulator
Types Of Materials
a substance with few free electrons is known as ____
insulator
Types Of Materials
Good insulators have a ____ valence shell, which leaves no free electrons to move fromm atom to atom
full/complete
Energy Band Gap
"highway" used by free electrons to move from atom to atom
conductance band
Energy Band Gap
where is the conductance band located
just above the valence shell
Energy Band Gap
is what materials do the valence shell and the conductance band overlap?
conductor
Energy Band Gap
a small gap between the valence shell and the conductance band is found is waht kind of material
semiconductor
Energy Band Gap
a large gap between the conductance band and the valence shell is found in what kind of material
insulator
Energy Band Gap
T/F
you need more energy to move free electrons thru a overlapped conductance band and valence shell?
False
overlapped conductance band and valence shell is considered a conductor and onyl requires a little energy to pass free electrons
