Fun With Carbon

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Fun With Carbon
CARBON BASIC’S
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Symbol of carbon is C
Atomic number of carbon is 6
Atomic weight of carbon is 12.0107
The electron configuration of
carbon is [He]2s22p2
 The word origin of carbon is, in
Latin carbo, : coal or charcoal.
 Carbon exists free in nature and
has been known since prehistoric
time.
Descriptions
Carbon’s standard state is solid at 298K or
25 degrees Celsius.
 In solid form Carbon is black as graphite
and colorless as a diamond.
 Carbon is a non-metal.
 Carbon is found widely in nature. It is
found in abundance in suns, stars,
comets, and atmospheres of many
planets.
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Allotropes of Carbon
Carbon is found in
three types in nature,
amorphous, graphite,
and diamond.
Diamond can be found
in volcanic vents such
as in South Africa.
They also can be
found on the ocean
floor off of the African
Coast.
. . .other Forms
Carbon is found
as carbon dioxide
in the
atmosphere and
is found in natural
water sources.
It can also be
found in rocks,
and also in coal
petroleum and
Forms Cont’
Carbon can also
occur as graphite
naturally.
Graphite is found in
New York and Texas
in the United
States, Russia,
Greenland, Mexico
and India.
FACTS
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Organic chemistry is the study of carbon and
its components.
Silicon can be used in place of carbon in
certain compounds, but unlike carbon it cannot
form stable compounds with long chains.
Carbons Isotopes
In 1961 the International Union of Pure
and Applied Chemistry adopted the isotope
carbon 12.
 Carbon 12 can be found on the periodic
table.
 Carbon 14 is used to date minerals such as
wood, archeological specimens.
 Carbon 13 can also be used for isotopic
labeling studies because it is also
radioactive, but not as stable
 A new form of carbon,
buckminsterfullerene or carbon 60, has be
found and is being researched in labs.

Uses Of Carbon
• Carbon is used in many life
processes.
• Diamond is used for cutting, drilling,
and also as bearings. It is also prized
as a gem stone.
• Graphite is used for melting metals
for rust protection and in pencils.
• Amorphous carbon is used for
removing tastes and odors.
COVALENT
BONDING
1) Covalent compounds generally have much lower
melting and boiling points than ionic compounds.
2) Covalent compounds are soft and squishy
(compared to ionic compounds, anyway).
3) Covalent compounds tend to be more flammable
than ionic compounds.
4) Covalent compounds don't conduct electricity in
water.
5) Covalent compounds aren't usually very soluble in
water.
Covalent Notebook
Methane, CH4
You will be familiar with
drawing methane using
dots and crosses
diagrams, but it is worth
looking at its structure a
bit more closely.
There is a serious mismatch between this
structure and the modern
electronic structure of
carbon,
1s2 2s2 2px1 2py1.
The modern structure
shows that there are only
2 unpaired electrons for
hydrogens to share with,
instead of the 4 which the
simple view requires.
Methane, CH4
You can see this more
readily by using the
electrons-in-boxes
notation.
Only the 2-level
electrons are shown.
The 1s2 electrons are
too deep inside the
atom to be involved
in bonding.
The only electrons
directly available for
sharing are the 2p
electrons. Why then
???
Promotion of an electron
When bonds are formed,
energy is released and the
system becomes more
stable. If carbon forms 4
bonds rather than 2, twice as
much energy is released and
so the resulting molecule
becomes even more stable.
There is only a small energy
gap between the 2s and 2p
orbitals, and so it pays the
carbon to provide a small
amount of energy to promote
an electron from the 2s to
the empty 2p to give 4
unpaired electrons.
The extra energy released
when the bonds form more
than compensates for the
initial input.
Hybridization
The electrons
rearrange themselves
again in a process
called hybridization.
This reorganizes the
electrons into four
identical hybrid
orbitals called sp3
hybrids (because they
are made from one s
orbital and three p
orbitals).
You should read "sp3"
as "s p three" - not as
"s p cubed".
Multiple Bonding
When two atoms share a single pair of electrons,
the bond is referred to as a single bond.
Atoms can also share two or three pairs of
electrons in the aptly named double and triple
bonds.
The first bond between two atoms is called the σ
(sigma) bond. All subsequent bonds are referred
to as π (pi) bonds.
In Lewis structures, multiple bonds are depicted
by two or three lines between the bonded
atoms.
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