Understanding Alkenes: Formulas, Naming, and Functional Groups

alkenes formula

The general formula for alkenes is CnH2n, where “n” represents the number of carbon atoms in the alkene chain

The general formula for alkenes is CnH2n, where “n” represents the number of carbon atoms in the alkene chain. Alkenes are a class of organic compounds that contain a carbon-carbon double bond. This double bond introduces unsaturation, meaning that alkenes have fewer hydrogen atoms compared to their corresponding alkane counterparts.

To name an alkene, you need to identify the longest chain of carbon atoms that contains the double bond. The name of the alkene is derived from the name of the corresponding alkane, but the “-ane” ending is replaced with “-ene” to indicate the presence of the double bond. The numbering of carbon atoms starts with the end closest to the double bond, and the position of the double bond is indicated by the lowest-numbered carbon atom involved in the bond.

For example, let’s consider the alkene with four carbon atoms, known as butene. The formula for butene is C4H8. It has a double bond between the second and third carbon atoms:

CH3-CH=CH-CH3

This alkene is called but-2-ene, as the double bond starts from the second carbon atom. The prefix “but” indicates the four carbon atoms in the chain, and the suffix “-ene” indicates the presence of the double bond.

It is important to note that alkenes can also have additional substituents or functional groups attached to the carbon chain. In such cases, the substituent names are indicated as prefixes before the parent alkene name.

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