Question

Write structural formula and name of 4$^{th}$ member of alcohol homologous series.

Hint:

4$^{th}$ alcohol = Butanol (C$_4$H$_9$OH).

Answer 1

Fourth Member of Alcohol Homologous Series:

Alcohols belong to a homologous series with the general formula C_nH_2n+1OH. Each successive member differs by a –CH₂ group.

First Four Members of Alcohol Series:
1. Methanol – CH₃OH
2. Ethanol – C₂H₅OH
3. Propanol – C₃H₇OH
4. Butanol – C₄H₉OH

Therefore, the fourth member of the alcohol homologous series is Butanol.

Molecular Formula:
C₄H₉OH

Structural Formula (1-Butanol):
CH₃ – CH₂ – CH₂ – CH₂ – OH

Explanation:
– It contains four carbon atoms.
– It has one hydroxyl (–OH) functional group.
– It differs from propanol by one –CH₂ unit.

Conclusion:
The fourth member of the alcohol homologous series is Butanol (C₄H₉OH), and its structural formula is CH₃–CH₂–CH₂–CH₂–OH.