The IUPAC name of the compound `CH_(2)=CH-CH(CH_(3))_(2)` is:

Options

A. 1,1-Dimethylprop-2-ene
B. 3-Methyl but-1-ene
C. 2-Vinylpropane
D. 1-Isopropylethylene

Explanation

To determine the IUPAC name of the compound `CH₂=CH-CH(CH₃)₂`, 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 compound. In this case, we can see that the longest chain consists of four carbon atoms.

### Step 2: Number the Carbon Chain
Next, we need to number the carbon chain. We start numbering from the end of the chain that is closest to the double bond. This ensures that the double bond gets the lowest possible number.

For the compound:
1. C1: CH₂ (part of the double bond)
2. C2: CH (part of the double bond)
3. C3: CH (with a methyl group attached)
4. C4: CH₃ (methyl group)

### Step 3: Identify Substituents
Now we need to identify any substituents attached to the main carbon chain. In this case, there are two methyl groups attached to the third carbon (C3).

### Step 4: Write the Name
Now we can write the IUPAC name based on the information we have:
1. The longest chain has 4 carbon atoms, which corresponds to "but".
2. There is a double bond between C1 and C2, which indicates that we should use "butene".
3. Since the double bond starts at C1, we denote it as "1-butene".
4. There are two methyl groups on C3, which we denote as "3,3-dimethyl".

Putting it all together, the IUPAC name of the compound is **3,3-dimethyl-1-butene**.

### Final Answer
The IUPAC name of the compound `CH₂=CH-CH(CH₃)₂` is **3,3-dimethyl-1-butene**.

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