Question:
Write the mechanism of the following reaction:
\[
\text{CH}_3\text{CH}_2\text{OH} \xrightarrow{H^+ \, 443\, \text{K}} \text{CH}_2 = \text{CH}_2
\]
Write the mechanism of the following reaction:
\[
\text{CH}_3\text{CH}_2\text{OH} \xrightarrow{H^+ \, 443\, \text{K}} \text{CH}_2 = \text{CH}_2
\]
Show Hint
Updated On: Feb 25, 2025
Hide Solution
Verified By Collegedunia
Solution and Explanation
The mechanism for the dehydration of ethanol (CH3CH2OH) to ethene (CH2=CH2) under acidic conditions involves the following steps:
Step 1: Formation of protonated alcohol (Fast step)
Ethanol (CH3CH2OH) reacts with the proton (H+) to form the protonated alcohol (ethyl oxonium ion).
CH3CH2OH + H+ → CH3CH2OH+
Step 2: Formation of carbocation (Slow step)
The protonated alcohol undergoes the loss of water to form a carbocation, which is the rate-determining step.
CH3CH2OH+ → CH3C+ + H2O
Step 3: Formation of ethene by elimination of a proton (Fast step)
The carbocation formed in Step 2 loses a proton to form ethene.
Overall reaction:
CH3C+CH2 → C2H4 (Ethene) + H+
Was this answer helpful?
0
0
Top Questions on Alcohols, Phenols And Ethers
- Can sodium ethoxide and t-butyl chloride be used for the preparation of t-butyl ethyl ether? Give suitable explanation. Justify your answer by suggesting the appropriate starting material required for preparation of t-butyl ethyl ether.
- CBSE CLASS XII - 2025
- Chemistry
- Alcohols, Phenols And Ethers
- Write the chemical equation for the preparation of anisole. Write the chemical equations of its reactions with:
i) Acetyl chloride
ii) Hydrogen iodide
iii) Mixture of conc.\ H$_2$SO$_4$ and conc.\ HNO$_3$- UP Board XII - 2025
- Chemistry
- Alcohols, Phenols And Ethers
- Write down the method of preparation of phenol. Write chemical equations of the reaction of phenol with the following: (i) Conc. HNO$_3$ (ii) Bromine water (iii) Zinc
- UP Board XII - 2025
- Chemistry
- Alcohols, Phenols And Ethers
- Write the structures of all possible isomers of alcohol having molecular formula C$_4$H$_{10$O.}
- UP Board XII - 2025
- Chemistry
- Alcohols, Phenols And Ethers
- What happens when — (write chemical equation only):
i) Phenol reacts with Br$_2$ water?
ii) Acetylation of phenol happens in the presence of pyridine?
iii) Phenol is heated with PCl$_5$?
iv) Phenol reacts with NaOH?
v) Vapour of the mixture of phenol and methyl alcohol is passed through hot thoria (ThO$_2$)?- UP Board XII - 2025
- Chemistry
- Alcohols, Phenols And Ethers
View More Questions
Questions Asked in CBSE CLASS XII exam
- Let \( A = \begin{bmatrix} 1 & -2 & -1 \\ 0 & 4 & -1 \\ -3 & 2 & 1 \end{bmatrix}, B = \begin{bmatrix} -5 \\ -2 \end{bmatrix}, C = [9 \ \ 7], \) which of the following is defined?
- What is the total number of possible matrices of order $3 \times 3$ with each entry as $\sqrt{2}$ or $\sqrt{3}$?
- Your school is organizing a road safety awareness workshop for students of class IX – XII. As the head boy of your school, draft a notice informing the students about the workshop. Include other necessary details. You are Ashna/Ashish. Put your notice in a box.
- CBSE CLASS XII - 2025
- Letter Writing
- Write a letter to the editor of a local daily highlighting the need for better public transportation in your city. You may use the given cues along with your own ideas to draft the letter. You are Sakshi / Sant, a resident of 46, C Colony, Crown Nagar.
- Challenges – Overcrowding in buses, poor maintenance, insufficient coverage, inadequate infrastructure
- Congestion due to private small time transport modes, unpredictable delays.
- Solutions – Increase frequency, regular maintenance, upgrading infrastructure, affordable fare.
- CBSE CLASS XII - 2025
- Letter Writing
- Calculate \( E_{\text{cell}} \) of a galvanic cell in which the following reaction takes place at 25°C:
\[ \text{Zn(s)} + \text{Pb}^{2+}(0.02M) \longrightarrow \text{Zn}^{2+}(0.1M) + \text{Pb(s)} \quad \text{[Given: } E^0_{\text{Zn}^{2+}/\text{Zn}} = -0.76V, \; E^0_{\text{Pb}^{2+}/\text{Pb}} = -0.13V, \; \log 2 = 0.3010, \; \log 4 = 0.6021, \; \log 5 = 0.6990 \text{]} \]- CBSE CLASS XII - 2025
- Electrochemistry
View More Questions