What is the correct order of the first four members of the homologous series of alcohols?

The correct order for the first four members of the homologous series of alcohols is indeed methanol, ethanol, propanol, and butanol. This series consists of organic compounds that contain a hydroxyl (-OH) functional group. Each subsequent member differs from the previous one by a -CH₂ unit, indicating a consistent pattern in their molecular structure.

Starting with methanol (CH₃OH), it is the simplest alcohol with one carbon atom. Ethanol (C₂H₅OH) follows with two carbon atoms. Propanol (C₃H₇OH) contains three carbon atoms, and butanol (C₄H₉OH) is the fourth member with four carbon atoms.

Recognizing the correct sequence is essential because it reflects the increasing complexity and size of these molecules, which directly influences their physical and chemical properties, such as boiling points and solubility. This orderly arrangement also demonstrates the systematic nature of organic chemistry, where members of a homologous series exhibit similar chemical behaviors due to their functional groups.