* Alkanes have only single bonds between carbon atoms (like methane, CH4).

* Alkenes have at least one double bond between carbon atoms.

* Alcohols contain a hydroxyl (-OH) group attached to a carbon atom.

The name "1-nonene" tells us:

* Non refers to a chain of nine carbon atoms.

* Ene indicates the presence of a double bond.

* 1- tells us the double bond is located between the first and second carbon atoms in the chain.