Hydrocarbon

A hydrocarbon is a type of chemical compound. It is made of only hydrogen and carbon atoms. They can be found in crude oil and are separated by fractional distillation (which means they are separated into different groups). The hydrogen and carbon are bonded with non-polar covalent bonds. Because of its lack of polar covalent bonds, hydrocarbons cannot create hydrogen bonds with water and are hydrophobic.

Hydrocarbon "families"

Hydrocarbons are grouped into "families" or "homologous series". There are five main families. The hydrocarbons in each family have a general formula and similar chemical properties, and similar trends in physical properties. This system was approved in 1892 by the International Congress of Chemists, meeting in Geneva.

Alkanes

Alkanes are the simplest hydrocarbons. Their general formula is C_nH_2n+2.

Alkane Name	Formula
Methane	CH₄
Ethane	C₂H₆
Propane	C₃H₈
Butane	C₄H₁₀
Pentane	C₅H₁₂
Hexane	C₆H₁₄
Heptane	C₇H₁₆
Octane	C₈H₁₈
Nonane	C₉H₂₀
Decane	C₁₀H₂₂

Alkenes

Alkenes are similar to alkanes. The main difference between them is that alkenes have a carbon to carbon double bond. The general formula for the alkenes is C_nH_2n.

Alkene Name	Formula
Ethene	C₂H₄
Propene	C₃H₆
Butene	C₄H₈
Pentene	C₅H₁₀
Hexene	C₆H₁₂
Heptene	C₇H₁₄
Octene	C₈H₁₆
Nonene	C₉H₁₈
Decene	C₁₀H₂₀

Note that there is no "Methene". Methene is not possible as alkenes require a carbon-carbon double bond and methane only has one carbon atom.

Alkynes

Alkynes have a carbon to carbon triple bond. C_nH_2n-2 is their general formula.

Alkyne Name	Formula
Ethyne (Acetylene)	C₂H₂
Propyne	C₃H₄
Butyne	C₄H₆
Pentyne	C₅H₈
Hexyne	C₆H₁₀
Heptyne	C₇H₁₂
Octyne	C₈H₁₄
Nonyne	C₉H₁₆
Decyne	C₁₀H₁₈

"Methyne" does not exist because of methane's one carbon atom.

Cycloalkanes

Cycloalkanes are isomers of alkenes. They have the same general formula (C_nH_2n), the only difference is that they do not have a carbon to carbon double bond.

Cycloalkane Name	Formula
Cyclopropane	C₃H₆
Cyclobutane	C₄H₈
Cyclopentane	C₅H₁₀
Cyclohexane	C₆H₁₂
Cycloheptane	C₇H₁₄
Cycloctane	C₈H₁₆
Cyclononane	C₉H₁₈
Cyclodecane	C₁₀H₂₀

Note that the alkene Ethene does not have a cycloalkane as it can only form a straight line.

Alkadiene

Alkadienes have two carbon to carbon double bonds. Their general formula is C_nH_2n-2. They are isomers of Alkynes.

In a similar manner, there can also exist alkatriene (three carbon to carbon bonds) and other forms. The versatile nature of Carbon's chemistry allows for a nearly infinite number of configurations and compounds.

Aromatic hydrocarbons

Aromatic hydrocarbons are aromatic organic molecules that form flat ring-shaped bonds. The most simplest of aromatic hydrocarbons are benzene and indole. They can have one ring, heterocyclic, like benzene or 2 rings, bicyclic like napthalene (primary ingredient in mothballs) or many rings, polycyclic like anthracene (red dye colourant). Their general formula is C_nH_2n-6, where n is a number greater than or equal to 6.