Alkenes

In alkanes there are only single bonds between carbon - carbon atoms. Also, there are hydrocarbons having double bonds between carbon - carbon atoms. The hydrocarbons of this type with one or more double bonds between carbon - carbon atoms are classified as alkanes. The molecular formula of the simplest alkene ethene is C2 H4 . Its structural formula is given below.

Due to the presence of double bonds between the carbon atoms, alkenes are more reactive than alkanes.

Derivatives of ethene
Chloroethene 

The compound derived by the displacement of a hydrogen atom in ethene by a chlorine atom is called chloroethene. The formula of chloroethene is C2 H3 Cl and its structure is given below.

Tetrafluoroethene 

The compound derived by the displacement of the four hydrogen atoms in ethene by four fluorine (F) atoms is known as tetrafluoroethene. Its formula is C2 F4 and the structure is as follows.

Ethene and derivatives of ethene are used to produce the polymers that we use in our day to life such as polythene, styrofoam and teflon.