Write IUPAC name of `Br-CH_(2)-CH_(2)-COOH`

Explanation

To write the IUPAC name of the compound `Br-CH₂-CH₂-COOH`, we can 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 three carbon atoms (C-C-C).

### Step 2: Identify the Functional Group
Next, we identify the functional group present in the compound. Here, we have a carboxylic acid group (-COOH) attached to the carbon chain. The presence of this group indicates that the compound is an acid.

### Step 3: Number the Carbon Chain
We need to number the carbon chain in such a way that the carboxylic acid group gets the lowest possible number. In this case, we start numbering from the end of the chain closest to the carboxylic acid group:
- The carboxylic acid carbon is at position 1.
- The second carbon is at position 2.
- The third carbon is at position 3.

### Step 4: Identify and Name the Substituents
In this compound, we also have a bromine (Br) substituent attached to the carbon chain. According to the numbering we established, the bromine is attached to the third carbon atom. We will use the prefix "bromo-" to indicate the presence of the bromine substituent.

### Step 5: Combine the Names
Now we can combine the information to write the full IUPAC name:
- The longest carbon chain with three carbons is called "propane."
- Since we have a carboxylic acid, we replace the "e" in "propane" with "oic acid," giving us "propanoic acid."
- We also include the bromo substituent at position 3, which gives us "3-bromopropanoic acid."

### Final Answer
The IUPAC name of the compound `Br-CH₂-CH₂-COOH` is **3-bromopropanoic acid**.

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