The structural formula for 3-hexene is CH3-CH2-CH=CH-CH2-CH3. A 3-hexene is one of many constitutional isomers of C6H12 and has a molecular weight of 84.16 grams per mole.
A 3-hexene is a six-carbon chain that contains one double bond between the third and fourth carbons. The double bond can either be a cis-double bond or a trans-double bond. If both of the attached carbons are on the same side of the double bond, it is a cis-double bond and can be written as (3Z)-3-hexene. If the attached carbons are on opposite sides of the double bond, it is a trans-double bond and can be written as (3E)-3-hexene.