Q14 of 55 Page 1

Define homologous series of organic compounds list its two characteristics. Write the name and formula of the first member of the series of alkenes. 3

The series which consists of similar structures and similar chemical properties in which the successive compounds differs by a CH2 group is termed as homologous series.

The two characteristics of homologous series are as follows:


1. The members of the homologous series consists of same general formula such as Alkanes have general formula CnH2n+2


2. The two adjacent homologues have a difference of molecular mass of 14 u.


(i) All the members of a homologous series can be represented by the same-general formula.


(ii) The difference in the molecular mass of any two adjacent homologues is 14 u.


The general formula for the alkenes is: CnH2n


The first member of the series of alkenes is: Ethane which has formula CH4


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(a) Write its electron configuration.


(b) State the group to which 'M' belongs?


(c) Is 'M' a metal or a non-metal?


(c) Write the formula of its chloride.

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(i) CH3COCH3 (ii) C2H5COOH