1. ALKANE
S

2. ALKANES
 are saturated hydrocarbons
 contain single bonds
 consist of hydrogen and carbon atoms
 its general chemical formula is
CnH2n+2

3. Alkane Formula
Methane CH4
Ethane C2H6
Propane C3H8
Butane C4H10
Pentane C5H12
Hexane C6H14
Heptane C7H16
Octane C8H18
Nonane C9H20
Decane C10H22
Undecane C11H24
Dodecane C12H26
Hexadecane C16H34
Icosane C20H42
Triacontane C30H62
Tetracontane C40H82
Pentacontane C50H102
Hexacontane C60H122

4. NAMING OF ALKANES
Branched chain alkanes are named by applying the following rules:
1. Determine the name of the parent compound by finding the longest
continuous chain of carbon atoms.
Pentane

5. 2. Number the longest continuou s chain beginning with the end closest to
the branch. Use these numbers to designate the location of the of the
groups or substituents at the branch.
1 2 3 4 5
2,3-dimethylpentane

6. 3. When two or more substituents are present on the same carbon atom,
use the no. of that carbon atom twice, List the substituents
alphabetically.
4-ethyl-4-methylheptane

7. 4. When two or more substituents are identical,indicate this fact by the use
of the prefixes: di, tri, tetra and so on. Commas are used to separate
numbers from each other.
2,2-dimethylpropane

8. EXAMPLES
butane 2,3-dimethylbutane
2,3,4-trimethylhexane

9. EXAMPLES
2,2,3, 2,2-dimethylbutane trimethyl butane

10. 2,2,3,3–tetramethylhexane
CH3 CH3
CH3 – CH2 – CH2 – C - C – CH3
CH3 CH3

11. 2,6–dimethyloctane
CH3
CH3 – CH2 – CH – CH2 - CH2 – CH2 – CH - CH3
CH3

12. I.Give the IUPAC name of the ff. alkanes:
1.
4.
5.
2.
3.

13. II. Give the structural formulas of the ff.
1.2,3-dichloro-3-methylhexane
2. 2,3-dimethyl-5-ethyldecane
3. 5-ethyl-2,3,6, trimethyl octane

14. ANSWERS:
I.
1.2-methylbutane
2.2,3-dimethyl-3-ethylpentane
3.2,4-dimethylheptane
4.3-ethylpentane
5.2,2-dimethylpropane

15. ANSWERS:
II. CH3
1. CH3 – CH – C – CH2 - CH2 – CH3
Cl Cl
2.
CH3 – CH – CH – CH2 - CH – CH2 – CH2 – CH2 – CH2 – CH3
CH3 CH3 C2H5
CH3 CH3
3. CH3 – CH – CH – CH2 - CH – CH – CH2 – CH3
CH3 C2H5