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Chemistry - Carbon and Organic Chemistry
Organic chemistry is the study of compounds that
contain C-C or C-H bonds. You might wonder, "Why devote a whole
field of study to just carbon compounds?"
The answer is two fold:
• There are more compounds that contain carbon than compounds
that don't.
• The compounds with carbon can be very large and complex.
Organic chemistry is a major part of our lives, from the simple
sugars and amino acids to the complex enzymes and huge DNA molecules.
Organic chemistry is involved in the development of the food you
eat; the clothes you wear; the plastics and polymers that are all
around you; the medicines you use; your fuels, pesticides, poisons,
soaps and detergents.
The properties of organic compounds differ from those of
inorganic compounds. Organic compounds have
• low melting points
• low boiling points
• soluble organic solvents rather than water
• poor electrical conductivity.
Organic reactions are usually slow and produce low yields of product
because of the many side reactions that can occur.
Although, there are millions of known organic compounds, the elements
they contain are relatively few. Besides, carbon and hydrogen, there
is oxygen, nitrogen, sulfur, phosphorus and the halogens.
The variety of organic compounds is due to the many different arrangements,
or structures, that are possible. The chemical and physical properties
of these compounds are related to the structures of their molecules.
Thus, the key to understanding organic chemistry is an understanding
molecular structure and chemical bonding.
Carbon
Remember, carbon has four valence electrons and can obtain a stable
configuration by forming four covalent bonds. Carbon can form single,
double or triple bonds and only a few elements can do this. Also,
carbon is unique in that it bonds easily with other carbon atoms,
while other elements rarely bond with like atoms. Thus, carbon can
form long chains, branched chains, rings and rings with chains for
a vast variety of compounds.
Hydrocarbons
Many organic compounds consist of only carbon and hydrogen atoms
and are known as hydrocarbons. Hydrocarbons are subdivided into
two groups-aliphatic hydrocarbons and aromatic hydrocarbons. The
aliphatic hydrocarbons that are acyclic (chains) or cyclic (rings)
and contain only sigma bonds are saturated hydrocarbons. Those that
have both sigma and pi bonds are known as unsaturated hydrocarbons.
The aromatic hydrocarbons are cyclic hydrocarbons that contain three
double bonds.
The aliphatic hydrocarbons consist of chains of carbon atoms with
hydrogen attached to the outsides of the chain. Since carbon can
form single, double and triple bonds three types of aliphatic hydrocarbons
are possible-alkanes, alkenes and alkynes.
Alkanes
Alkanes are hydrocarbons in which there are only single covalent
bonds between the carbon atoms. The general formula for alkanes
is Cn H2n+2, where n is the number of carbon atoms in the chain.
The length of the carbon chain tends to affect the physical properties
such as boiling point and melting point due to the variation in
strength of the dipersion forces.
Naming alkanes is simple, just choose the prefix that indicates
the number of carbons in the chain and add the suffix -ane to the
end.
Alkenes
Alkenes are compounds in which there is at least one double covalent
bond between the carbon atoms. The general formula for alkenes is
Cn H2n, where n is the number of carbon atoms in the chain. To name
alkenes, indicate where the double bond is by numbering the carbon
chain starting with the end closest to the double bond. Then use
a prefix to indicate the number of carbons in the chain and add
the suffix -ene to the end. For chains that contain two double bonds,
list the location of the double bonds and add the suffix -adiene
to the end.
Alkynes
Alkynes are compounds in which there is at least one double covalent
bond between the carbon atoms. The general formula for alkenes is
CnH2n-2, where n is the number of carbon atoms in the chain. To
name alkynes, indicate where the triple bond is by numbering the
carbon chain starting with the end closest to the triple bond. Then
use a prefix to indicate the number of carbons in the chain and
add the suffix -yne to the end.
Since, organic compounds are every where and a major part of chemistry.
Therefore, it is important that you know as much as possible about
organic chemistry. If you would like to know more about chemical
reactions or chemical equations go to Mr. Causey's World or http://yourCHEMcoach.com
Article Source: http://EzineArticles.com/?expert=Darrell_Causey
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