Organic+-+Homologous+series

 =Homologous Series=

A homologous series is a family of organic compounds containing a particular characteristic group and exhibiting similar properties. For example, the compounds given below belong to the alcohol family. CH3OH methyl alcohol (methanol) CH3CH2CH2OH propyl alcohol (1-propanol) CH3CH2.CH2.CH2OH butyl alcohol (1-butanol) 

Characteristics of a Homologous Series
All members of a homologous series exhibit some common characteristics. They are: CH4 C2H6 C3H8 C4H10 Methane Ethane Propane Butane
 * All the members of a homologous series can be represented by a common general formula, as they have the same functional group. For example, alkanes can be represented by the formula CnH2n+2.
 * Each member of a homologous series has a common difference of -CH2 from the next higher or lower member.
 * Common general methods of preparation exist for all members of the series.
 * All members exhibit similar chemical behavior.
 * An increase in molecular mass of members within a homologous series show a similar regular gradation of the physical properties, such as, physical state, melting and boiling points etc.

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