how the nomenclature of compound having morethan 20 carbon atoms can be done

Follow the basic rules,

1. Find the longest chain

2. find the smallest branching chain and number from the side from where the branching gets the smaller number

3. Follow the series in which the order of naming is taken .. i.e acids > ketones > ether > aldehyde > alcohol ........

4. Name the compounds in the alphabetical order.

5. if it is a cyclic structure use the keyowrd 'cyclo' and follow the above rules.

Please approve !!

It matters if they are in the longest chain or present as substituent.

If they are in longest chain then it is not in sylllabus for IIT-JEE entrance exam.

And if they are present as substituent then they can be named.

Well, there are specific names for each number..

like for

one - meth

two - eth

five - pent

similarly,

13- tridec

15- pentadec

20-eicos

30-triacont

so, there are different names, however at this level you need to memorize all.. till 12 is okay..

Please Approve!!