The document discusses the classification and naming of hydrocarbons. It defines hydrocarbons as organic compounds containing only carbon and hydrogen. Alkanes are a type of hydrocarbon that contain only single carbon-carbon bonds. Alkanes can be straight chain (normal) or branched chain. The document outlines the systematic naming conventions for alkanes based on the number of carbons, including prefixes and denoting branch positions with numbers.

1. SHRI. GOVINDRAO MUNGHATE COLLEGE,
KURKHEDA
Presented By-
Dr. Ganesh D. Satpute
Department of Chemistry

2. HYDROCARBON
Organic compound contain only Carbon & Hydrogen.
Classification of Hydrocarbon

3. Alkanes
Alkanes are hydrocarbons that contain only carbon-carbon single bonds.
Alkanes in which the carbons are connected in a straight chain are called Normal
Alkanes.
Ex. n-hexane
Alkanes that are branched are called Branched Chain Alkanes.
Ex. 2-methyl-pentane
C C C C C C
H
H
H
H H H H H
H
H
H
H
H
H
C C C C C H
H
H
H
C
H H H
H
H
H
H
H
H
H

4. International Union of Pure and Applied Chemistry
Alkanes always have the ending –ane with prefix indicating the
name and number of carbon atom
Methane (CH4)
Ethane (C2H6)
Propane (C3H8)
Butane (C4H10)
Pentane (C5H12)
Hexane (C6H14)
Heptane (C7H16)
Octane (C8H18)
Nonane (C9H20)
Decane (C10H22)
CH4
CH3 CH3
CH3 CH2 CH3
CH3 CH2 CH2 CH3
CH3 CH2 CH2 CH2 CH3
CH3 CH2 CH2 CH2 CH2 CH3
CH3 CH2 CH2 CH2 CH2 CH2 CH3
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH3
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH3
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH2 CH3

5. • If there are two possible chains with the same
number of carbons, use the chain with the most
substituents.
C
CH3
CH2
CH3
CH CH2 CH2 CH3
CH CH2 CH3
H3C
H3C
=>
Rule –
1. Identify the longest Chain – Parent chain

6. 2) Number the Carbons
• Start at the end closest to the first attached group.
• If two substituent's are equidistant, look for the next
closest group.
1
2
3 4 5
6 7
CH
H3C
CH3
CH
CH2CH3
CH2 CH2 CH
CH3
CH3

7. CH3 CH2 CH CH2 CH2 CH CH2 CH3
CH3 CH2 CH3
3) If two different substituent present on position then the
substituent which came alphabetically first get lower no.
8 7 6 5 4 3 2 1
Ethyl- - C2H5
Methyl- - CH3
3-ethyl-6-methyloctane
CH3 CH2 CH CH2 CH2 CH CH2 CH3
CH3 CH2 CH3

8. 4) Use di-, tri-,tetra-, penta-, etc., for multiples of same
substituent.
5) More different substituents are present write them
alphabetical order.
6) combine number and name of substituent with parent
name, separating with hyphen .
7) For compounds with a single ring, add the prefix “cyclo-
” to the root name for the alkane comprising the ring.

9. CH3 CH2 CH CH2 CH2 CH CH2 CH3
CH3 CH2 CH3
Parent chain- octane
Two substituent, methyl with 6 position and
ethyl with 3 position
8 7 6 5 4 3 2 1
3-ethyl-6-methyloctane
CH3 CH2 CH CH2 CH2 CH CH2 CH3
CH3 CH2 CH3