Alkane , Alkene , Alkyne

Alkane

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Alkane-

Aliphatic saturated hydrocarbons are called Paraffin or alkane.
All the Carbon atoms in alkane are linked by single bond.
The general formula of alkane is CnH2n+2 where n is the number of carbon atoms.
The suffix used for this series is ‘ane’
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

Ex-

Alkene –

Those aliphatic unsaturated hydrocarbons which contain at least one carbon carbon double bond (C=C )are called alkene or olefin .
General formula of alkene is CnH2n
Their suffix is ‘ene’
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

Alkyne

Those aliphatic unsaturated hydrocarbons which contain at least one carbon carbon triple bond , are called alkynes or acetylenes.
The general formula of alkyne is CnH2n-2
Their suffix is ‘yne’
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.