Identify the pairs of compounds that represents position isomerism.

1. CH3-CH2-CH2-CH2-OH

2. 

3. 

4. 

5. CH3-CH2-O-CH2-CH3

6. CH3-O-CH2-CH2-CH3

7. 


When two or more compounds differ in position of substituent atom or functional group on the carbon skeleton, they are position isomers. In the given structures, I and II; III and IV, and VI and VII are position isomers.