Notice: Trying to access array offset on value of type null in /home/murreeroad/ on line 1131
Write a detailed note on classification of organic compounds. - Questions and Answers
0 like 0 dislike
in Chemistry by (36.5k points)
Write a detailed note on classification of organic compounds.

1 Answer

0 like 0 dislike
by (36.5k points)
Answer. All known organic compounds have been broadly divided into two categories depending upon their carbon skeleton. These are:

(i)     Open chain or acyclic compounds.

(ii) Closed chain or cyclic compounds.

(i)     Open chain or acyclic compounds.

Acyclic compounds contain open chains of carbon atoms in their molecules. These chains may be either straight or branched. For example,

 (a)      Straight chain compounds are those in which carbon atom links with other carbon atoms or other atoms through a single, double or triple bonds forming a straight chain, such as

          I  I  I  I  I  I


          I  I  I  I  I  I                               H3C-CH2-CH2-CH3  

          Straight chain                                    Straight chain (n-Butane)

(b)      Branched chain compounds are those in which there is a branch along a straight chain, such as:




    Branched chain                          Branched chain (isobutane)

Open chain compounds are also called aliphatic compounds.

(ii) Closed chain or Cyclic compounds

Closed chain or cyclic compounds contain one or more closed chains, i.e., the carbon atoms at the end of the chain are not free. They are further divided into two classes:

(a)      Homocyclic or carbocyclic compounds.

(b)      Heterocyclic compounds.

 (a) Homocyclic or Carbocyclic compounds.

Homocyclic or carbocyclic compounds contain rings which are made up of only one kind of atoms, i.e., carbon atoms. These are further divided into two classes:

•         Aromatic compounds

•         Alicyclic compounds

Aromatic compounds: These organic compounds contain at least one benzene ring in their molecule. A benzene ring is made up of six carbon atoms with three alternating double bonds. They are called aromatic because of aroma. Aroma means smell. Examples,


              Benzene                   Napthehatene

They are also called benzenoid compounds.

Alicyclic or non-benzenoid compounds: Carbocyclic compounds which do not have benzene ring in their molecules are called alicyclic or non-benzenoid compounds. For example


                     Cydobutan                     Cyclohexane

Heterocyclic compounds

Cyclic compounds that contain one or more atoms other than that of carbon atoms in their rings are called heterocyclic compounds.


                               Thiophene        Pyridine

The above classification may be summarized as follows:
Welcome to Free Homework Help, where you can ask questions and receive answers from other members of the community. Anybody can ask a question. Anybody can answer. The best answers are voted up and rise to the top. Join them; it only takes a minute: School, College, University, Academy Free Homework Help

19.4k questions

18.3k answers


3.2k users

Free Hit Counters