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).
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
• Atom H from alkanes can be replaced by other atoms, especially the halogen group.
• Replacement 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.
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.
The reaction of incorporation of simple• molecules into large molecules.
simple molecules called monomers undergo• polymerization, while the result is called a polymer.
• polymerization of alkenes occurs by an addition reaction.
The process• can be described as follows:
First open bond that formed the group with two unpaired electrons.
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”
Isomers are compounds that have the same molecular formula but have different structures or configurations.
Structures related to the way the atoms are bonded to each other, while the configuration associated with the spatial arrangement of atoms in the molecule.
isomers can be divided into 2, namely:
o isomer structure: keisomeran due to differences in structure.
o isomer space: keisomeran due to differences in the configuration (the same molecular formula and structure).
Can be divided into three, namely:
• isomer framework: if the same molecular formula but the parent chain (framework atoms) are different.
• isomer position: if the molecular formula and its parent chain (framework atoms) are the same but the position of branch / group different successor.
• functional group isomers
Can be divided into 2, namely:
o isomer geometry: keisomeran due to differences in direction (orientation) certain groups of molecules with the same structure.
o optical isomers.
A. isomers on Alkanes
o Classified isomer structure ie the difference carbon atom skeleton. The longer the carbon chain, the more likely isomers.
o Added the number of isomers is unregulated. Also note that by no means all the possible isomers exist in reality.
o For example: can be made 18 possible isomers of C 8 H 18, but it does not mean there are 18 compounds with the molecular formula C 8 H 18.
o systematic way to find the number of possible isomers in alkanes:
B. isomers in alkenes
Can be keisomeran structure and space.
a) Structural isomers.
structural isomers in alkenes can occur due to differences in the position of the double bond or due to differences in the atomic frame C.
began in the butene isomer which has 3 isomer structure. Another example is the alkene with 5 atom C.
b) Geometric isomers.
space on the alkene isomer geometric keisomeran classified as follows: due to differences in the placement of the groups around the double bond.
o isomer to 2-butene. Known to 2 types of 2-butene, namely cis-2-butene and trans-2-butene. Both have the same structure but different configurations (clusters orientation in space).
o In the cis-2-butene, the two methyl groups located on the same side of the double bond; instead on trans-2-butene, the two opposing methyl group.
Not all compounds that have a double bond in the carbon atom (C = C) has a geometric isomer. The compound will have a geometric isomer if the two C atoms bonded dual binding of different groups.
C. isomers on the alkyne
classified alkyne isomer isomer on the framework and positioning.
The alkyne there are no geometric isomers.
starting isomer contained in butuna having two isomers.