unsaturated compound

In organic chemistry, an unsaturated compound is a chemical compound that contains carbon - carbon pi bonds such as an alkene or an alkyne. In a saturated compound these pi bonds are removed by the addition of hydrogen and no multiple bonds are present. Alkanes are examples of saturated compounds. It is in this sense that fatty acids are classified as saturated or unsaturated, according to their iodine number.
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An organic compound with molecules containing one or more double bonds.