Organic chemistry is the scientific study of branching chemistry on the structure, properties, composition, reactions, and synthesis of organic compounds. Organic compounds are constructed mainly by carbon and hydrogen, and may contain other elements such as nitrogen, oxygen, phosphorus, halogen and sulfur
history
Organic chemistry as a science is generally agreed was initiated in 1828 with the organic synthesis of urea by Friedrich Woehler, who accidentally vaporize a solution of ammonium cyanate NH4OCN.
progress from time to time increased.
Hydrocarbon compounds
Hydrocarbons are the most simple carbon compounds. From the name, hydrocarbon compounds are carbon compounds that are composed of hydrogen and carbon atoms. In everyday life we encounter many hydrocarbon compounds, such as kerosene, gasoline, natural gas, plastics and others.
Until now has been known for more than 2 million of hydrocarbons. To facilitate the study of hydrocarbons so much, experts mengolongkan hydrocarbon based arrangement of carbon atoms in the molecule.
Based on the arrangement of carbon atoms in the molecule, carbon compounds are divided into two major categories, namely compound aliphatic and cyclic compounds. Aliphatic hydrocarbons are carbon compounds chain opens its C and C it allows branched chain. Based on the amount of the bond, aliphatic hydrocarbons, aliphatic compounds are divided into saturated and unsaturated.
- The compound is a saturated aliphatic C chain aliphatic compounds it contains only single bonds only. This group is called alkanes.
Examples of saturated aliphatic hydrocarbons
Hydrocarbon Properties
Highlights include: a) Physical Properties
b) Chemical Properties Related to chemical reactions.
1) The reactions of the Alkanes
Alkanes considered difficult substances react so-called paraffin which means little affinity. The most important reaction of alkanes is combustion reactions, substitution and cracking (cracking).
Explanation:
a. Combustion
o Complete combustion of alkanes to produce gas CO 2 and water vapor, while the incomplete combustion produces CO gas and water vapor, or soot (carbon particles).
b. Substitution or change
· Atomic H from alkanes can be replaced by other atoms, especially the halogen group.
· Replacement of the H atom by atom or another group called substitution reaction.
· One of the most important substitution reactions of alkanes are halogenated alkanes, namely the replacement of H atoms by halogen atoms, especially chlorine (chlorination).
· Chlorination can occur if the alkane is reacted with chlorine.
c. Cracking or cracking
§ Cracking is breaking the carbon chains into pieces shorter.
§ Cracking can occur when the alkane is heated at high temperature and high pressure without oxygen.
§ This reaction can also be used to make alkenes from alkanes. It can also be used to create hydrogen gas from alkanes.
2) Reactions on Alkenes
o alkenes more reactive than alkanes. This is because the double bond C = C.
o alkene reactions mainly occur at the double bond. Important reactions of alkenes include: combustion reactions, addition and polymerization.
Explanation:
a. Combustion
§ As with alkanes, alkenes low interest flammable. If burned in the open air, alkenes produce more soot than alkanes. This happens because the alkene have higher levels of C than alkanes, so that combustion demands / needs more oxygen.
§ Complete combustion of alkenes produce CO 2 and water vapor.
b. Adducts (addition = saturation)
o The most important reactions of alkenes are addition reactions that bond saturation reactions.
c. Polymerization
· The reaction of incorporation of simple molecules into large molecules.
· Simple molecules called monomers undergo polymerization, while the result is called a polymer.
· Polymerization occurs by addition reactions of alkenes.
· The process can be explained as follows:
ü First open bond that formed the group with two unpaired electrons.
ü unpaired electrons then form a bond between the groups so as to form a chain.
3) reactions on alkyne
o These reactions are similar to the alkyne alkene; to saturate double bonds, requiring alkyne reagent 2 times more than the alkene.
o The most important reactions of alkenes and alkynes are addition reactions with H 2, the addition of the halogen (X 2) and the addition of the acid halide (HX).
o In addition reaction gas HX (X = Cl, Br or I) to alkenes and alkynes Markovnikov rules apply, namely:
"If the C atom bonded dual binding of different amounts of H atoms, the atom X will be bound to the atom C a few atoms bind H"
"If the C atom bonded to duplicate the number of H atoms bind together a lot, then the atom X will be bound to C atoms that have the most long-chain C"
The names of hydrocarbon molecules are based on the number of carbon atoms that make up the molecule and the type of bond between them. The prefix of the molecule's name is based on number of carbon atoms. For example, a chain of six carbon atoms would be named hex-.
It would be a good idea to commit this table to memory early in your organic chemistry studies.Organic Hydrocarbon Prefixes
Prefix Number of
Carbon atoms Formula
meth- 1 C
eth- 2 C2
prop- 3 C3
but- 4 C4
pent- 5 C5
hex- 6 C6
hept- 7 C7
oct- 8 C8
non- 9 C9
dec- 10 C10
