`C_2H_5OHoverset("Conc".H_2SO_4)underset(443K)rarr Z`
In the above reaction `Z` is identified as

Options

A. `C_2H_5-O-C_2H_5`
B. `C_2H_5CHO`
C. `CH_2=CH_2`
D. `C_2H_5HSO_4`

Answer

To solve the question regarding the reaction of ethanol (C2H5OH) with concentrated sulfuric acid (H2SO4) at a temperature of 443 K, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants and Conditions**:
- The reactant is ethanol (C2H5OH).
- The reagent is concentrated sulfuric acid (H2SO4).
- The reaction temperature is 443 K.

2. **Understand the Reaction Type**:
- At elevated temperatures, concentrated sulfuric acid acts as a dehydrating agent. This means it will facilitate the removal of water (H2O) from the ethanol.

3. **Dehydration Process**:
- When ethanol undergoes dehydration, the hydroxyl group (–OH) from one carbon and a hydrogen atom (H) from the adjacent carbon are removed, leading to the formation of a double bond (C=C) between the two carbon atoms.

4. **Formation of the Product**:
- The reaction can be represented as:
\[ C_2H_5OH \xrightarrow{Conc. H_2SO_4, 443K} C_2H_4 + H_2O \]
- Here, C2H4 is ethylene (or ethene), which is the product formed after the dehydration of ethanol.

5. **Identify the Correct Option**:
- Among the provided options, ethylene (C2H4) is the correct product formed at the specified conditions. Therefore, Z is identified as ethylene.

### Final Answer:
Z is identified as **ethylene (C2H4)**.

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