The IUPAC name of `CH_(3)CH_(2)CH_(2)undersetunderset(CH_(2)OH)(|)(CH)-CH_(2)CH_(3)` is:

Options

A. 3 - Propyl butan - 1 - ol
B. 2 - ethylpentan - 1 -ol
C. 3 - methylhydroxyhexane
D. 2 - ethyl - 2 - propyl ethanol

Explanation

To determine the IUPAC name of the compound `CH3CH2CH2CH(CH2OH)(CH)CH2CH3`, we will follow these steps:

### Step 1: Identify the longest carbon chain
First, we need to identify the longest continuous chain of carbon atoms in the structure. In this case, the longest chain consists of 5 carbon atoms.

### Step 2: Number the carbon chain
We will number the carbon chain starting from the end closest to the functional group (the hydroxyl group, -OH). This ensures that the functional group receives the lowest possible number.

1. CH3 (1)
2. CH2 (2)
3. CH2 (3)
4. CH (4) - this carbon has the -OH group
5. CH2 (5)

### Step 3: Identify the functional group
The functional group present is -OH, which indicates that this compound is an alcohol. The suffix for alcohols is "-ol". Since the -OH group is on carbon 4, we will indicate that in the name.

### Step 4: Identify substituents
Next, we need to identify any substituents attached to the longest chain. In this case, there is an ethyl group (C2H5) attached to carbon 2 of the main chain.

### Step 5: Combine the information to form the IUPAC name
Now, we can combine the information we have gathered:
- The longest chain has 5 carbon atoms, which is called "pentane".
- The substituent is an ethyl group on carbon 2.
- The alcohol functional group is on carbon 4.

Putting it all together, the IUPAC name of the compound is **2-ethyl-4-pentanol**.

### Final Answer
The IUPAC name of `CH3CH2CH2CH(CH2OH)(CH)CH2CH3` is **2-ethyl-4-pentanol**.

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