Write IUPAC name of `CH_(3)CH_(2)CH_(2)COOH`

Explanation

To find the IUPAC name of the compound `CH₃CH₂CH₂COOH`, we will follow these steps:

### Step 1: Identify the Longest Carbon Chain
The first step is to identify the longest continuous carbon chain in the molecule. In this case, the longest chain consists of four carbon atoms.

### Step 2: Number the Carbon Chain
Next, we need to number the carbon chain. Since we have a carboxylic acid group (-COOH) present, we will start numbering from the end of the chain that is closest to the carboxylic acid group. This ensures that the carboxylic acid gets the lowest possible number.

1. The carbon attached to the -COOH group is carbon 1.
2. The numbering continues as follows:
- Carbon 1: -COOH
- Carbon 2: CH₂
- Carbon 3: CH₂
- Carbon 4: CH₃

### Step 3: Determine the Base Name
The base name of the compound is derived from the number of carbon atoms in the longest chain. Since there are four carbon atoms, the base name is "butane."

### Step 4: Identify the Functional Group
The functional group present in the compound is the carboxylic acid group (-COOH). In IUPAC nomenclature, the suffix for carboxylic acids is "-oic acid."

### Step 5: Combine the Information
Since the carboxylic acid group is on carbon 1, we can combine the base name and the suffix. The full IUPAC name of the compound is "butanoic acid."

### Final Answer
The IUPAC name of `CH₃CH₂CH₂COOH` is **butanoic acid**.

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