Carbon compounds can be classified into two types.
1:-Trivial or common system
2:-IUPAC system
1:-Trivial or common system
- The name of HCOOH is formic acid because the first time it is found in ants and this ant's Latin name is Formica.
- Methane's name is marsh gas because it is found in marshy areas.
- In mammals' urine NH2CONH2 find. Later that name puts urea.
2:-IUPAC System(International union of pure and applied chemistry)
The nomenclature of IUPAC of any carbonic compound has three parts.
(a) Word root (b) Suffix (c) Prefix
(a) Word root:-
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Word root |
The Word root of the IUPAC name indicates the number of carbon atoms in the longest possible continuous carbon chain also known as the parent chain chosen by a set of rules.
(b) Suffix:-
Suffix are two types
(1) Primary Suffix (2) Secondary Suffix
(1)Primary Suffix:-
- (―) 'ane'
- (≓) 'ene'
- (☰) 'yne'
(2) Secondary Suffix:-
(c) Prefix:-
A prefix is also two types
(1) Primary Prefix (2) Secondary Prefix
(1) Primary Prefix
This is used to put the difference between cyclic compound and acyclic compound.
(2) Secondary Prefix
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Secondary Prefix |
IUPAC Rules
Secondary Prefix+Primary Prefix+Word Root+Primary Suffix+Secondary Suffix
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Example of Saturated Hydrocarbon |
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Example of Branched-Chain Saturated Hydrocarbon |
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Example of Unsaturated Hydrocarbon Containing Double Bond |
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Example of Unsaturated Hydrocarbon Containing Triple Bond |
Isomers
- In inorganic chemistry, a given molecular formula represents only one compound Ex:-H2SO4.
- Inorganic chemistry, however, a given molecular formula can represent two or more different compounds.
- The organic compound has the same molecular formula but a different structure are known as isomers
Ex:-Consider an organic compound C4H10 called butane.
(i) First, all the four carbon atoms are joined in a continuous straight chain.
(ii) In the second case, three carbons atoms can be put in the straight-chain and the fourth carbon atom can be joined in the side chain.
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Iso-butane |
Note:-
- We find that both n-butane(normal- butane) & iso-butane have the same molecular formula(C4H10) but different structures. They are called isomers.
- The butane fuel present in LPG cylinders is a mixture of both its isomers:-n-butane and iso-butane(LPG also contain a smaller amount of propane ðane)