Write the IUPAC name of `(CH_(3))_(2)CH-COOH`

Explanation

To determine the IUPAC name of the compound `(CH₃)₂CH-COOH`, we will follow these steps:

### Step 1: Identify the Structure
The given compound can be represented structurally as follows:
- The `(CH₃)₂CH` part indicates that there is a carbon chain with two methyl groups attached to a central carbon atom.
- The `-COOH` indicates the presence of a carboxylic acid functional group.

### Step 2: Determine the Longest Carbon Chain
We need to find the longest continuous carbon chain that includes the carboxylic acid group:
- The longest carbon chain here consists of three carbon atoms: `CH₃-CH-COOH`.

### Step 3: Number the Carbon Chain
To give the carboxylic acid group the lowest possible number, we will start numbering from the end nearest to the `-COOH` group:
- The numbering will be as follows:
- Carbon 1: `COOH`
- Carbon 2: `CH`
- Carbon 3: `CH₃`

### Step 4: Identify Substituents
In this structure, we have a methyl group attached to the second carbon:
- The substituent is a methyl group at position 2.

### Step 5: Write the IUPAC Name
Now we can combine all the information:
- The longest chain has three carbons, which is called "propane."
- The carboxylic acid group is at position 1, so we use the suffix "oic acid."
- There is a methyl group at position 2, so we include that in the name.

Putting it all together, the IUPAC name of the compound is:
**2-methylpropanoic acid**

### Final Answer
The IUPAC name of `(CH₃)₂CH-COOH` is **2-methylpropanoic acid**.

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