Structure and Nomenclature of Unsaturated Fatty Acids

Unsaturated fatty acids contain one or more double bonds. A common method for designating fatty acids gives the 

The presence of a double bond in the hydrocarbon chain gives rise to geometrical isomerism, which is due to restricted rotation around carbon-carbon double bonds and is exemplified by fumaric and maleic acids. 

Geometry of saturated, trans monounsaturated, and cis monounsaturated chains. 

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