Alkanes

Alkanes are the organic compounds that consist of single-bonded carbon and hydrogen atoms. The formula for Alkanes is CnH2n+2CnH2n+2, subdivided into three groups – chain alkanes, cycloalkanes, and the branched alkanes.These are comprised of a series of compounds that contain carbon and hydrogen atoms with single covalent bonds.This group of compounds consists of carbon and hydrogen atoms with single covalent bonds. Also, comprises of a homologous series having a molecular formula of C n H 2 n+2

Read about Physical Properties of Alkanes Group.

The simple alkane methane contains one carbon atom and CH 4 as its molecular formula. As this compound have just single covalent bonds only, therefore, its structural formula is

 

Alkanes

 

In a long chain alkane molecule, additional carbon atoms are attached to each other with the help of a single covalent bond. Each atom is attached to the sufficient hydrogen atoms to develop a total of four single covalent bonds. This long chain structure is known as octane. An eight-carbon alkane has a molecular formula – C 8H 18 and structural formula-

 

Alkanes

Alkyl Groups

When a substituent like halogen bonds to an alkane molecule, one carbon-hydrogen bond of the molecule gets converted to carbon-substituent bond. It can be understood with an example- A new compound known as chloromethane is formed when methane reacts with chlorine. The new compound is composed of CH 3 group that is bonded to a chlorine atom.

Alkyl Groups

When an alkane having hydrogen is removed from one bond, it is called an alkyl group. This Alkyl group is often denoted by the letter R same as halogens represent by the letter X. Here is  methane‐chlorine reaction that can be generalized as

Alkyl Groups

 

 


Practise This Question

Hydrogen is evolved by the action of cold dil. HNO3 on