Markovnikov rule is applicable to

Options

A. `CH_(2)=CH_(2)`
B. `CH_(3)-CH_(2)-CH_(3)`
C. `CH_(3)-CH=CH-CH_(3)`
D.

Answer

To determine the applicability of Markovnikov's rule to a given compound, we need to follow these steps:

### Step 1: Identify the Compounds
First, we need to look at the compounds provided in the question. We will analyze each compound to see if they contain an alkene (a carbon-carbon double bond) and whether they are symmetrical or unsymmetrical.

### Step 2: Check for Unsymmetrical Alkenes
Markovnikov's rule states that when an unsymmetrical alkene reacts with a reagent (like H-X), the more electronegative part of the reagent will attach to the more substituted carbon atom. This means we need to identify if the alkene is unsymmetrical, which occurs when the two carbon atoms of the double bond have different substituents.

- **Compound 1:** Check if both sides of the double bond have the same or different groups.
- **Compound 2:** Repeat the same check.
- **Compound 3:** Again, check for symmetry.
- **Compound 4:** Check if there are different groups attached to the double bond.

### Step 3: Analyze Each Compound
1. **Compound 1:** If both carbons of the double bond have similar groups (e.g., both have hydrogen), then it is symmetrical, and Markovnikov's rule does not apply.
2. **Compound 2:** If both carbons have the same substituents, it is also symmetrical, and Markovnikov's rule does not apply.
3. **Compound 3:** If there is no double bond present, then Markovnikov's rule is not applicable.
4. **Compound 4:** If there are different groups attached to the double bond (for example, one carbon has a methyl group and the other has a hydrogen), it is unsymmetrical, and thus, Markovnikov's rule is applicable.

### Step 4: Conclusion
Based on the analysis, we conclude that Markovnikov's rule is applicable only to the fourth compound, where the double bond has different groups attached to each carbon.

### Final Answer
Markovnikov's rule is applicable to the fourth compound.

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