The reaction : `CH_3CH_2OH underset(453K) overset(95% H_2SO_4)to CH_2=CH_2+H_2O` is an example of

Options

A. dehydration
B. dehydrogenation
C. hydration
D. decarboxylation

Explanation

To determine the type of reaction represented by the equation:

\[ \text{CH}_3\text{CH}_2\text{OH} \xrightarrow{453K, 95\% \text{H}_2\text{SO}_4} \text{CH}_2=\text{CH}_2 + \text{H}_2\text{O} \]

we need to analyze the reaction step by step.

### Step 1: Identify the Reactants and Products
- The reactant is ethanol (\( \text{CH}_3\text{CH}_2\text{OH} \)).
- The products are ethylene (\( \text{CH}_2=\text{CH}_2 \)) and water (\( \text{H}_2\text{O} \)).

### Step 2: Understand the Reaction Conditions
- The reaction is conducted at a temperature of 453 K and in the presence of concentrated sulfuric acid (95% \( \text{H}_2\text{SO}_4 \)).
- Concentrated sulfuric acid acts as a dehydrating agent.

### Step 3: Analyze the Type of Reaction
- In this reaction, a water molecule is removed from ethanol, resulting in the formation of ethylene.
- This process of removing water from a molecule is known as dehydration.

### Step 4: Confirm the Reaction Type
- Dehydration reactions are characterized by the elimination of water.
- Since the products include water as a by-product, we can confirm that this reaction is indeed a dehydration reaction.

### Conclusion
The reaction is an example of **dehydration**.

### Final Answer
The correct option is **dehydration reaction**.

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