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Saturated vs Unsaturated Hydrocarbons: Definition, Differences, Examples  

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Definition of Saturated Hydrocarbons

Saturated hydrocarbons are the most basic types of hydrocarbons, consisting completely of single bonds that remain hydrogen-saturated.

  • Acyclic saturated hydrocarbons, often known as alkanes, have the general formula CnH2n+2The more general formula is CnH2n+2(1-r) , where r is the number of rings.
  • There are no double or triple bonds between the carbon atoms in saturated hydrocarbons, as well as all carbon atoms form four unique covalent bonds.
  • The name “saturated” refers to the structure’s saturation of hydrogen atoms, that makes them the simplest as well as least polar organic molecules.
  • Saturated hydrocarbons can be found in either a linear or branched form, depending on the structure’s complexity.
  • These hydrocarbons are found predominantly in petroleum products as well as other fossil fuels.
  • Since saturated hydrocarbons burn with a blue, non-sooty flame, they are employed as fuel in cars as well as other engines.
  • Saturated hydrocarbons exhibit the substitution process since they resist other reactions such as hydrogenation as well as oxidative addition.
  • In comparison to unsaturated hydrocarbons, saturated hydrocarbons have a lower carbon concentration since the number of hydrogen atoms is relatively high.
  • They’re also more stable as well as less reactive, as well as they can withstand nucleophile as well as electrophile attacks.
  • Saturated hydrocarbons are divided into two groups: acyclic alkanes as well as cycloalkanes.
  • Saturated hydrocarbons include methane, butane, propane, as well as cyclohexane, among others.

Definition of unsaturated hydrocarbons

Unsaturated hydrocarbons are hydrocarbons that have double or triple bonds between their carbon atoms.

  • Alkenes, that have the general formula CnH2n , are unsaturated hydrocarbons with double bonds, whereas alkynes, that have the general formula CnH2n-2 , are unsaturated hydrocarbons with triple bonds.
  • The word unsaturated refers to the fact that the molecules can be saturated by adding extra hydrogen atoms.
  • Unsaturated hydrocarbons, like saturated hydrocarbons, can be found in straight-chain linear, branched, or aromatic forms.
  • Since aromatic rings are created by the delocalization of double bonds between numerous carbon atoms, all aromatic hydrocarbons are unsaturated hydrocarbons.
  • Unsaturated hydrocarbons, with the exception of aromatic compounds, are more reactive as well as undergo numerous addition reactions on multiple bonds.
  • The degree of unsaturation, that is a measure of the amount of -bonds present in a molecule, can be used to express the unsaturation of hydrocarbons.
  • Since there are fewer hydrogen atoms in unsaturated hydrocarbons, they have a higher carbon concentration than saturated hydrocarbons.
  • Since unsaturated hydrocarbons have a lower hydrogen content, they produce a yellow flame, that reduces the flame’s moisture content.
  • Since unsaturated hydrocarbons, like most hydrocarbons, are non-polar, their structures are held together by a weak van der Waal’s attraction.
  • Unsaturated hydrocarbons have a distinct nomenclature than saturated hydrocarbons since the position of the double or triple bonds is indicated by adding numbers to the prefix.
  • Ethane, acetylene, benzene, butadiene, as well as other unsaturated hydrocarbons are examples.

Saturated vs Unsaturated Hydrocarbons: Definition, Differences, Examples  

Key Differences between Saturated and Unsaturated Hydrocarbons

(Saturated vs Unsaturated Hydrocarbons)

Saturated Hydrocarbons Examples


  • Methane is the most basic aliphatic hydrocarbon, consisting of a single carbon atom bound to four hydrogen atoms in a single bond.
  • It has the chemical formula CH4 as well as is a saturated hydrocarbon with all four covalent bonds attached to four separate hydrogen atoms.
  • Methane is a simple hydrocarbon that burns with a pale blue flame that is mildly bright. It’s less combustible as well as more stable than other comparable chemicals.
  • In methane, all four carbon-hydrogen bonds have a bond length of 1.09 * 10 -10 as well as a bond angle of 109.5° . It has three sp3 hybridized orbitals as well as is a tetrahedral molecule.
  • Methane is a valuable fossil fuel that is widely used as a biogas for cooking. It’s also a key member of the greenhouse gas family, as well as it’s one of the main contributors to global warming.

Unsaturated Hydrocarbons Examples


  • Acetylene, often known as ethyne, is a two-carbon unsaturated hydrocarbon having the formula C2H2.
  • It’s an alkyne with a triple carbon-to-carbon link as well as a single carbon-to-hydrogen covalent bond.
  • Since the carbon-carbon triple bond places all four atoms in the same straight line with a bond angle of 180°, the molecule has a linear structure.
  • One of the triple bonds is a -bond, while the other two are -bonds that are weaker.
  • Oxyacetylene gas welding as well as cutting provide about 20% of the total acetylene found in the environment.
  • Acetylene’s carbon-carbon triple bond is energy rich, allowing it to be employed as a good substrate for bacteria.



Saturated Hydrocarbons vs Unsaturated Hydrocarbons Citations 

  1. Gautam AD, Pant M and Adhikari NR (2017). Comprehensive Chemistry Part 2. Heritage Publishers and Distributors. Kathmandu, Nepal.
  2.  Methane” PubChem, Accessed 21 February, 2021.
  3. National Center for Biotechnology Information. PubChem Compound Summary for CID 6326, Acetylene. Accessed Apr. 8, 2021. 



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