3. Presented by,
Simi
Physical Science

4. Organic compounds with
same molecular formula but
having different structural
formula are called isomers
and the phenomenon is
called isomerism.

5. Based on the differences in the structures
isomerism can be classified into various types.
 Chain Isomerism
 Functional group Isomerism
 Position Isomerism
 Metamerism

6. Chain isomerism occurs due to the
difference in the carbon chain.
Examples for Chain Isomerism
 BUTANE
CH3- CH2- CH2- CH3
 2-METHYL PROPANE CH3-
CH- CH2- CH3
CH3

7. Functional group isomerism occurs
due to the difference in functional group.
EXAMPLES
• ETHANOL
CH3- CH2- OH
• DIMETHYL ETHER
CH3- O- CH3

8. Position isomerism occurs when isomers
differ in the position of the functional groups in
the same carbon chain.
EXAMPLES
o 1-BUTANOL
CH3-CH2-CH2-CH2-OH
o 2-BUTANOL
CH3-CH-CH2-CH3
OH

9. Metamerism occurs due to the difference in
the number of carbon atoms in the alkyl
groups on either sides of a functional group.
EXAMPLES
ETHOXY BUTANE
CH3-CH2-O-CH2-CH2-CH2-CH3
METHOXY PENTANE
CH3-O-CH2-CH2-CH2-CH2-CH3