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Organic Chemistry

Hydrocarbon

Definition and meaning of Hydrocarbon in chemistry.

Hydrocarbon is an organic compound made up entirely of carbon and hydrogen atoms. Hydrocarbons form the structural backbone of organic chemistry and range from simple gases to complex ring systems.

In more detail

Hydrocarbons are classified by their bonding pattern: saturated hydrocarbons (alkanes) contain only single C-C bonds, while unsaturated hydrocarbons contain carbon-carbon double bonds (alkenes) or triple bonds (alkynes). A separate class, aromatic hydrocarbons, contains stabilized ring systems with delocalized pi electrons, such as benzene. Because carbon atoms can bond to form long chains, branches, and rings, hydrocarbons exist in an enormous variety of structures. They are the major components of fossil fuels (petroleum, natural gas, coal) and serve as the raw feedstock for fuels, plastics, and solvents.

Key facts

FieldOrganic Chemistry
General formula (alkanes)CnH2n+2
Main classesSaturated (alkanes), unsaturated (alkenes, alkynes), aromatic
Complete combustion productsCarbon dioxide (CO2) and water (H2O)
Example

Methane, the simplest hydrocarbon and chief component of natural gas, consists of one carbon atom bonded to four hydrogen atoms in a tetrahedral shape.

Frequently asked questions

What is the difference between saturated and unsaturated hydrocarbons?

Saturated hydrocarbons (alkanes) contain only single carbon-carbon bonds and hold the maximum possible number of hydrogen atoms. Unsaturated hydrocarbons contain at least one carbon-carbon double bond (alkenes) or triple bond (alkynes), which means fewer hydrogen atoms per carbon.

Why are hydrocarbons important as fuels?

Most hydrocarbons burn readily in oxygen, releasing large amounts of energy and producing carbon dioxide and water when combustion is complete, which is why petroleum and natural gas hydrocarbons are widely used as fuels.

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