In the acid catalyzed dehydration of alcohols to alkenes, the intermediate species formed is

Options

A. Free radical
B. Carbocation
C. Carbanion
D. Carbene

Answer

To solve the question regarding the intermediate species formed in the acid-catalyzed dehydration of alcohols to alkenes, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reaction**:
The dehydration of alcohols involves the removal of a water molecule (H₂O) from the alcohol to form an alkene. This reaction is typically catalyzed by an acid, such as sulfuric acid (H₂SO₄).

**Hint**: Remember that dehydration means the removal of water from a compound.

2. **Protonation of Alcohol**:
The first step in the mechanism involves the protonation of the alcohol. The lone pair of electrons on the oxygen atom of the alcohol (e.g., CH₃CH₂OH) attacks a proton (H⁺) from the acid (H₂SO₄). This forms an oxonium ion (CH₃CH₂OH₂⁺), where the oxygen now carries a positive charge.

**Hint**: Look for how the alcohol interacts with the acid to form a charged species.

3. **Formation of Carbocation**:
The oxonium ion (CH₃CH₂OH₂⁺) is unstable and can lose a water molecule (H₂O). When water is removed, a carbocation (CH₃CH₂⁺) is formed. This carbocation is a positively charged carbon species.

**Hint**: Identify the species that results from the loss of water from the oxonium ion.

4. **Formation of Alkene**:
The carbocation can then undergo deprotonation. A hydrogen atom from the adjacent carbon can be removed (as H⁺), and the electrons from the C-H bond shift to form a double bond between the two carbon atoms. This results in the formation of the alkene (CH₂=CH₂).

**Hint**: Consider how the carbocation can rearrange or lose a proton to form a double bond.

5. **Conclusion**:
The intermediate species formed during the acid-catalyzed dehydration of alcohols is a **carbocation**.

**Final Answer**: The intermediate species formed is a **carbocation**.