Advertisements
Advertisements
Questions
What is a homologous series?
What is a homologous series? Explain with an example.
Advertisements
Solution 1
Homologous series is a group of organic compounds with a similar structure and similar chemical properties in which the successive compounds differ by a CH2 group.
Solution 2
A homologous series is a series of carbon compounds that have different numbers of carbon atoms but contain the same functional group.
For example, methane, ethane, propane, butane, etc. are all part of the alkane homologous series. The general formula of this series is CnH2n+2.
Methane CH4
Ethane CH3CH3
Propane CH3CH2CH3
Butane CH3CH2CH2CH3
It can be noticed that there is a difference of -CH2 unit between each successive compound.
APPEARS IN
RELATED QUESTIONS
Write the molecular formula of two consecutive members of homologous series of aldehydes. State which part of these compounds determines their
- physical and
- chemical properties
Write the molecular formula of first two members of homologous series having functional group −Br.
Give the structural formula for 1, 2-dichloroethane
By how many carbon atoms and hydrogen atoms do any two adjacent homologues differ?
Write the molecular formula of the third member of the homologous series of carbon compounds with general formula CnHO2n+1OH.
The number of carbon atoms present in the molecule of fifth member of the homologous series of alkynes is:
(a) four
(b) five
(c) six
(d) seven
Propane and ethane are ______.
.
Haloalkanes react with alkalies to produce alcohol. Give the equation for the preparation of the second member of the homologous series of alcohol. State under what condition the reaction occurs.
While going in an increasing order there is a rise in the molecular mass of the consecutive members of the homologous series by _______.
Cyclohexane : Cyclic hydrocarbon : : Isobutylene : _______
Find the odd one out and give its explanation.
As one ascends in any homologous series, physical properties change gradually.
Complete the following chart by using examples given in brackets.
(isobutylene, cyclohexane, propane, cyclohexene, cyclopentane, benzene, propyne, isobutane, propene)
| Straight chain hydrocarbons | Branched chain hydrocarbons | Cyclic hydrocarbons |
Which of the following pairs can be the successive members of a homologous series?
A carbon compound ‘A’ having melting point 156K and boiling point 351K, with molecular formula C2H6O is soluble in water in all proportions.
- Identify ‘A’ and draw its electron dot structure.
- Give the molecular formulae of any two homologues of ‘A’.
Define Homologous series.
Name and draw the electron dot structure of first homologue of alkynes series.
Name the third homologue of aldehydes.
