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| Method of Naming of Hydrocarbons |
Method of Naming of Alkane Hydrocarbons
There are 11
million hydrocarbons therefore it is very difficult to study them therefore
scientists issued a scheme to give systematic name to the organic compounds is
called nomenclature.
Nomenclature or chemical Nomenclature or Nomenclature system
such system
or method of naming to give a name to the organic compounds are called
nomenclature. There are two ways to give a name to the organic compounds.
- Common name or trivial name
- IUPAC system
- Common name or trivial name
such ordinary name given to the
organic compounds without reference of its structure, composition and
properties is called common name or trivial name. This name can be applied to
the all isomers and the prefixes (n)
normal, iso and neo is used to
differentiate b/w these isomers. Such as
- IUPAC system
there are 11 million organic
compounds. So common name cannot be applied to all compounds and it is very
difficult to study them therefore in since 1947 at England the scientist issued
a scheme called IUPAC means International Union of Pure and Applied
Chemistry to give a systematic name to the organic compounds on the basis
of their structure and properties. Thus it is defined as “such a systematic name given to the organic compounds on the basis
of structure and properties by applying the IUPAC rules is called IUPAC system.”. Due to IUPAC system now it very easy
to understand its structure and even properties of compounds due to its name.
IUPAC system of naming straight chain alkanes
IUPAC
system of naming straight chain alkanes are
divided into
two parts.
- Root name
- Suffix
Root name
the name which is determined the
number of carbon atoms in a longest continuous chain containing the functional
group is called root name. The root name is derived from the Greek word and the
suffix is added with it then a name completes. The suffix is written at last
and Greek name is written first.
General Concept:
Root name + Suffix
Meth + ane
รจ Methane
Suffix
the name which is written at the last
with a parent name is called suffix. It is used for both straight and branched
chain compounds. If the suffix is ane then it showed that the compounds has a
single covalent bond and is saturated and if the suffix is yne or ene then it
showed that the compound is having double or triple bond and is unsaturated.
IUPAC system of naming branch chain alkanes
IUPAC
system of naming branched chain alkanes are divided into four rules;
Rule no.1: Select the longest continuous chain of
carbon atoms which determines the root name or parent name of alkane. Such as
Rule no.2: Start the numbering from the side where
the branch or substitute is nearer and position the number to a substitute or
branched chain. Such as
Rule no.3: write the branched or substitute with
a number which shows or designates the location of branched in a chain that
where it is. The number of position is written first than name of branches is
written then longest continuous chain name is written. The number of position
and branched name is separated by hyphen (–).
Rule no.4: When same substitute or branched are
present in the same chain then the prefixes like di, tri and tetra are added.
Position of number of each substitute is shown and is separated by commas. Such
as
