Alkenes & Their Reactions [Chemistry only]

2 min read · part of the full Exam Guide

Structure of alkenes

General formula: $\text{C}_n\text{H}_{2n}$ , two fewer hydrogens than the alkane with the same number of carbons
The functional group is C=C, and it is the functional group that decides how a compound reacts

Alkene	Formula	Where the double bond is
Ethene	$\text{C}_2\text{H}_4$	between the two carbons
Propene	$\text{C}_3\text{H}_6$	between carbons 1 and 2
Butene	$\text{C}_4\text{H}_8$	between carbons 1 and 2
Pentene	$\text{C}_5\text{H}_{10}$	between carbons 1 and 2

Displayed formulae of ethene, propene, butene and pentene with the C=C double bond drawn as a double line

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Structure of alkenes
Combustion
Addition reactions

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