Other Organic Hydrocarbons

Alkanes are only one type of hydrocarbon. Alkanes are saturated. This means each carbon only forms single bonds with other carbon atoms. Each carbon has 4 single bonds.The bonds can be with any combination of carbon and other elements. The general formula of alkanes is CnH2n+2.The formulas and names for the first 10 alkanes are listed below.
 

Alkenes are another kind of hydrocarbon. They are similar to alkanes in that they contain only hydrogen and carbon. They are different because they are unsaturated. In alkenes, there is at least one double carbon : carbon bond. A single bond involves the sharing of a pair (2) electrons so a double bond means two pairs of electrons (4) are shared between the two carbon atoms. The general formula of for all alkenes is CnH2n.

Alkynes are still a third kind of hydrocarbon. They are hydrocarbons and they are unsaturated. They are different from alkenes because they have at least one triple carbon : carbon bond. A triple bond involves three pairs (6) of electrons. The general formula for all alkynes is CnH2n-2. Below are electron dot diagrams of corresponding alkanes, alkenes and alkynes.

The system of naming the alkenes and alkynes is very similar to the naming of the alkanes. The only difference is the ending. Instead of ending in -ane, the alkenes and alkynes end in -ene and -yne. See the table below for the names.
 

There are numerous possible arrangements of the carbon and hydrogens in hydrocarbons. it is possible for compounds containing 4 or more carbons to arrange themselves in numerous different structures. Isomers are compounds with the same chemical formula but with a different structural formula. While isomers have the same chemical formula, their different structural formulas result in different chemical and physical properties. An example of two isomers of C4H10 is below.

Some Derivitives of Hydrocarbons

Alcohols - alkanes with an -OH group in place of one of the hydrogens. The general formula of an alcohol is R-OH, where R is a hydrocarbon.

Carboxylic Acids - alkanes with a carboxyl group attached. The carvoxyl group has a formula of -COOH. Both oxygens are bonded to the carbon. One oxygen forms a double bond with the carbon. The other forms a single bond with the carbon and has the hydrogen attached to it. The general formula of a carboxylic acid is R-COOH.

Esters - formed from a reaction between alcohols and carboxylic acids.

Amino acids - hydrocarbons that have a COOH group on one side and a -NH2 group on the other side. Amino acids are what protein consists of.

Numerous materials can be synthesized from petroleum products, such as:

• detergents
• pesticides
• pharmaceuticals
• plastics
• paints
• fabrics
• rubber

Alkanes are mainly used for burning. Alkenes and alkynes have the double and triple bonds that are more reactive. Various petrochemicals can be synthesized by addition reactions.

Polymers

Some carbon compounds have the ability to "link up" to form long chains of repeating units. These types of molecules are called polymers. There are numerous examples of polymers in nature including DNA, a polymer of nucleic acids, protein, a polymer of amino acids, and starch, a polymer of glucose.

There a numerous examples of synthetic polymers. The basic repeating unit usually consists of a hydrocarbon or hydrocarbon derivitive with a double bond. Some examples include:

• polyethylene - a polymer of ethene (C2H4)
• teflon - a polymer of tetrafluoroethene (C2F4)
• pvc (polyvinylchloride)- a polymer of chloroethene (C2H3Cl)