What is the general formula for an aliphatic alcohol ? (R=alkyl group)

Options

A. R-H
B. R-OH
C. R-CHO
D. R-COOH

Answer

To find the general formula for an aliphatic alcohol, we can follow these steps:

### Step 1: Understand the Structure of Alcohols
Alcohols are organic compounds that contain one or more hydroxyl (-OH) groups. The presence of this functional group is what defines an alcohol.

**Hint:** Remember that the hydroxyl group (-OH) is crucial for identifying alcohols.

### Step 2: Identify the Alkyl Group
In the formula, "R" represents an alkyl group. Alkyl groups are derived from alkanes by removing one hydrogen atom. They can vary in size and structure, such as methyl (CH3-), ethyl (C2H5-), and so on.

**Hint:** Alkyl groups can be straight-chain or branched, but they all derive from alkanes.

### Step 3: Combine the Alkyl Group with the Hydroxyl Group
The general formula for an aliphatic alcohol can be expressed as:
\[ \text{R-OH} \]
Where "R" is the alkyl group and "-OH" is the hydroxyl group.

**Hint:** The "-OH" group is what makes the compound an alcohol, so ensure it is included in the formula.

### Step 4: Write the General Formula
Putting it all together, the general formula for an aliphatic alcohol is:
\[ \text{C}_n\text{H}_{2n+1}\text{OH} \]
This formula indicates that for every "n" carbon atoms in the alkyl group, there are "2n+1" hydrogen atoms, plus one hydroxyl group.

**Hint:** The formula CnH2n+1OH can help you determine the number of hydrogen atoms based on the number of carbon atoms in the alkyl group.

### Final Answer
The general formula for an aliphatic alcohol is:
\[ \text{C}_n\text{H}_{2n+1}\text{OH} \]