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  1. Aliphatic saturated hydrocarbons are called Paraffin or alkane.
  2. All the Carbon atoms in alkane are linked by single bond.
  3. The general formula of  alkane  is CnH2n+2  where n is the number  of carbon atoms.
  4. The suffix used for this series is ‘ane’
  5. IUPAC name of paraffin  is written as  Alk+ ane = Alkane

Alkyl  groups & their names – 

i) These are univalent groups or radicals obtained by removal of one hydrogen atom from a molecule of paraffin.

ii) The symbol ‘R’ is often used to represent an alkyl group .

iii) Their general formula is CnH2n+1

iv) Their  IUPAC name is written as,    Alkane – ane + yl = Alkyl


Alkene –

  1.  Those aliphatic unsaturated hydrocarbons which contain at least one carbon carbon double bond (C=C )are called alkene or olefin .
  2.  General formula  of alkene is CnH2n
  3.  Their suffix is ‘ene’
  4.  IUPAC name of alkene is written as,  Alk+ ene= Alkene   or  Alkane -ane+ene = Alkene

Ex. i)  CH2=CH2 or C2H4 

      Common name- Ethylene 

      IUPAC name-  Eth+ ene = Ethene

ii) C3H6

       Common name- Propylene 

      IUPAC name-  Prop + ene = Propene

If there are two carbon  carbon double bonds (C=C) in unsaturated hydrocarbon , then their general formula is CnH2n-2 & their  IUPAC name is  Alkadiene

If there are three carbon carbon double bonds (C=C ) in unsaturated hydrocarbon, then their  general formula is CnH2n-4 & their  IUPAC name is  Alkatriene


  1. Those aliphatic unsaturated hydrocarbons which contain at least one carbon carbon triple bond , are called alkynes or acetylenes.
  2. The general formula of alkyne is CnH2n-2
  3. Their  suffix  is ‘yne’
  4.  IUPAC name  is written as [ alk + yne] = Alkyne   or  [Alkane -ane+yne = Alkyne]

Ex. i)   C2H2 

      Common name- Acetylene 

      IUPAC name-  Eth+ yne = Ethyne

ii) C3H6

     IUPAC name-  Prop+ yne = Propyne

Unsaturated alkyl group  & their names –

Groups obtained by removing one hydrogen atom from unsaturated hydrocarbons (alkene or alkyne ) are called unsaturated alkyl group  or typical alkyl groups.

Other Examples –