What happens when (write chemical equation in each case)
ethanol is heated with excess conc . `H_(2)SO_(4)` at 443 K?

Explanation

When ethanol (C₂H₅OH) is heated with excess concentrated sulfuric acid (H₂SO₄) at 443 K, a dehydration reaction occurs. This process leads to the formation of ethene (C₂H₄) as the primary product. Here’s the step-by-step breakdown of the reaction:

### Step 1: Protonation of Ethanol
When ethanol is mixed with concentrated sulfuric acid, the hydroxyl (OH) group of ethanol is protonated. This forms an oxonium ion.

**Chemical Equation:**
\[ \text{C}_2\text{H}_5\text{OH} + \text{H}_2\text{SO}_4 \rightarrow \text{C}_2\text{H}_5\text{OH}_2^+ + \text{HSO}_4^- \]

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