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Karnataka Board PUCPUC Science 2nd PUC Class 12

Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.

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Question

Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.

Chemical Equations/Structures
Short Answer
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Solution

In the presence of conc. acids such as H3PO4 and H2SO4 alcohols undergo dehydration to yield alkenes.

\[\ce{\underset{Ethanol}{H3C - CH2 - OH} ->[conc{.} H+/\Delta] \underset{Ethene}{CH2 = CH2} + H2O}\]

The mechanism for this reaction is:

Step 1: Protonation of ethanol:

Step 1: Formation of carbocation:

Step 3: Formation of ethene and regeneration of proton:

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Chapter 7: Alcohols, Phenols and Ethers - Exercises [Page 223]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 7 Alcohols, Phenols and Ethers
Exercises | Q 7.19 | Page 223

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Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.


Write the mechanism of acid dehydration of ethanol to yield ethene.


Write the mechanism of acid dehydration of ethanol to yield ethene.


Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.


Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.


Write the mechanism of acid dehydration of ethanol to yield ethene. 


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