The IUPAC name of the compound
`CH_3 - underset(underset(CH(CH_3)_2)|) CH - CH_3` is

Options

A. 2-isopropylpropane
B. isobutane
C. 2, 3-dimethylbutane
D. 2, 3-dimethylhexane.

Answer

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

### Step 1: Identify the Longest Carbon Chain
First, we need to identify the longest continuous carbon chain in the compound. In this case, the longest chain consists of 4 carbon atoms.

### Step 2: Number the Carbon Chain
Next, we will number the carbon chain. We will number it in such a way that the substituents (methyl groups) receive the lowest possible numbers.

- If we start numbering from the left (C1 to C4), we have:
- C1: CH₃
- C2: CH(CH₃)₂ (which is a carbon with two methyl groups attached)
- C3: CH
- C4: CH₃

This gives us:
- C2 has two methyl groups (C3 and C4).
- C3 has one hydrogen and is connected to C2 and C4.

### Step 3: Identify the Substituents
From our numbering, we see that there are two methyl groups attached to the second carbon and one methyl group attached to the third carbon.

### Step 4: Write the IUPAC Name
Now we can write the IUPAC name based on the information we have gathered:
- The longest chain has 4 carbons, which corresponds to "butane."
- There are two methyl groups on the second carbon and one on the third carbon, which corresponds to "2,3-dimethyl."

Putting it all together, the IUPAC name of the compound is **2,3-dimethylbutane**.

### Final Answer
The IUPAC name of the compound `CH₃ - CH(CH₃)₂ - CH - CH₃` is **2,3-dimethylbutane**.

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