The IUPAC name for `CH_(3)CH_(2)CH (CH = CH_(2)) CH_(2)CH_(2)CH_(3)` is

Options

A. 4-Ethenylheptane
B. 3-n-propylhex-1-ene
C. 3-Ethenylheptane
D. None of these

Explanation

To determine the IUPAC name for the compound `CH3CH2CH(CH=CH2)CH2CH2CH3`, we can follow these steps:

### Step 1: Identify the Longest Carbon Chain
First, we need to identify the longest continuous carbon chain in the compound. The structure can be represented as follows:

```
CH3-CH2-CH(CH=CH2)-CH2-CH2-CH3
```

Counting the carbon atoms, we can see that there are 6 carbon atoms in the longest chain.

### Step 2: Number the Carbon Chain
Next, we need to number the carbon chain. We will number the chain from the end closest to the double bond to give it the lowest possible number.

```
1 2 3 4 5 6
CH3-CH2-CH(CH=CH2)-CH2-CH2-CH3
```

In this case, the double bond (C=C) is located between carbon 1 and carbon 2.

### Step 3: Identify Substituents
Now, we need to identify any substituents on the main carbon chain. In this case, there is an ethyl group on carbon 3.

### Step 4: Write the Name
Now we can write the IUPAC name. The main chain has 6 carbon atoms (hexane), and there is a double bond starting at carbon 1 (hex-1-ene). We also have an ethyl group on carbon 3, which we denote as 3-ethyl.

Putting it all together, the IUPAC name for the compound is:

**3-ethylhex-1-ene**

### Final Answer
The IUPAC name for `CH3CH2CH(CH=CH2)CH2CH2CH3` is **3-ethylhex-1-ene**.

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