Dehydration of Alcohols

Q.

Consider the following reaction:C₂H₅OH + H₂SO₄ → Product.

Among the following, which one cannot be formed as a product under any conditions?

1. Ethylene

2. Acetylene

3. Diethyl ether

4. Ethyl -hydrogen sulphate

Q. Aqueous sulphuric acid reacts with 2-methyl-1-butene to give predominantly

1. Isobutyl hydrogen sulphate
2. 2-methyl-2-butanol
3. 2-methyl-1-butanol
4. Secondary butyl hydrogen sulphate

Q.

Which carbocation is more likely to be formed in
dehydration of

1. 

2. 

3. 

4. 

Q.
To achieve the above conversion, the reagents used will be:

1. $O_3/H_2{O}_2,O{H}^{-}/\Delta$
2. $\text{HBr, alc. KOH},{\text{O}}_3,{\text{LiAlH}}_4,{\text{H}}^{+}/\Delta$
3. $HBr,t-BuOK,O_3,KMn{O}_4,\Delta$
4. $HCl,KMn{O}_4\left(cold\right),H^{+}/\Delta$

Q. Arrange the following alcohols in the decreasing order of their ease of dehydration with $H_{2}S{O}_4$

1. (iii)>(ii)>(iv)>(i)>(v)
2. (iii)>(ii)>(i)>(iv)>(v)
3. (ii)>(iii)>(iv)>(i)>(v)
4. (iii)>(ii)>(iv)>(v)>(i)

Q. The relative rate of acid catalyzed dehydration of following alcohols would be:

1. III > I > IV > II
2. III > IV > I > II
3. I > III > IV > II
4. III > IV > II > I

Q. When vapour of alcohol is passed over Ag powder at ${300}^{\circ }C$ the product is isobutene. Alcohol in this reaction will be:

$\left(a\right)C{H}_3-C{H}_2-\stackrel{OH}{\stackrel{|}{CH}}-C{H}_3\left(b\right)C{H}_3-2-\underset{C{H}_3}{\underset{|}{\stackrel{OH}{\stackrel{|}{C}}}}-C{H}_3$

$\left(c\right){}_{\underset{C{H}_3}{╱}}^{\stackrel{C{H}_3}{╲}}CH-\underset{C{H}_3}{\underset{|}{\stackrel{OH}{\stackrel{|}{C}}}}-C{H}_3\left(d\right)C{H}_3-\underset{C{H}_3}{\underset{|}{\stackrel{OH}{\stackrel{|}{C}}}}-C{H}_3$

1. $a$
2. $b$
3. $c$
4. $d$

Q.

Which carbocation is involved in the above reaction ?

1. 

2. 

3. Both

4. None

Q.
In the given reaction, the total number of alkenes formed (including stereoisomers) is:

Q.

Which reacts rapidly with Lucas reagent ?

1. $C{H}_2=CHC{H}_{2}OH$

2. $(C{H}_3{)}_{3}COH$

3. $Both\left(a\right)and\left(b\right)$

4. $C{H}_{3}C{H}_{2}OH$

Q. In $S_{N}2$ reaction the configuration of the reactant is $R$, after the reaction the configuration of the product remains same i.e. $R$

1. True
2. False

Q. Ethylene glycol on heating with con. $H_{2}S{O}_4$ gives mainly:

1. 
2. 
3. 
4. 

Q. When 3, 3-dimethyl-2-butanol is heated with $H_{2}S{O}_4$ the major product obtained is

1. cis and trans isomers of 2, 3-dimethyl-2-butene
2. 3, 3-dimethyl-1-butene
3. 2, 3-dimethyl-2-butene
4. 2, 3-dimethyl-1-butene

Q. What is the correct product of the following reaction?

1. 
2. 
3. 
4. 

Q. What is the correct product of the following reaction?


The major product is :

1. 
2. 
3. 
4. 

Q.

Consider the following reaction:C₂H₅OH + H₂SO₄ → Product.

Among the following, which one cannot be formed as a product under any conditions?

1. Ethylene

2. Acetylene

3. Diethyl ether

4. Ethyl -hydrogen sulphate

Q.

For the above reaction , the major product (A) is :

1. 
2. 
3. 
4. 

Q. Write the product of the following reaction:

1. 
2. 
3. 
4. 

Q. $C{H}_3-\stackrel{\stackrel{C{H}_3}{|}}{\underset{\underset{C{H}_3}{|}}{C}}-X\stackrel{alc.KOH}{\to }$
'X' is halogen
Choose the correct statement for the above reaction is :

1. $\beta$ elimination reaction
2. product will be 2-methylpropene
3. Dehydrohalogenation reaction
4. All of the above.

Q. $C{H}_3-\stackrel{\stackrel{C{H}_3}{|}}{\underset{\underset{C{H}_3}{|}}{C}}-X\stackrel{alc.KOH}{\to }$
'X' is halogen
Choose the correct statement for the above reaction is :

1. $\beta$ elimination reaction
2. product will be 2-methylpropene
3. Dehydrohalogenation reaction
4. All of the above.

Q.
In the above reaction, the major product is shown which is formed through the intermediate (carbocation) given below:
Which bond will migrate to form the above product?

1. q
2. r
3. p
4. s

Q. Aqueous sulphuric acid reacts with 2-methyl-1-butene to give predominantly

1. Isobutyl hydrogen sulphate
2. 2-methyl-2-butanol
3. 2-methyl-1-butanol
4. Secondary butyl hydrogen sulphate

Q.

Identify the product D in the following series of reaction

$C{H}_{3}COOH\stackrel{LiAl{H}_4}{\to }A\underset{443K}{\overset{H^{+}}{\to }}B\stackrel{B{r}_2}{\to }C\underset{KOH}{\overset{alc.}{\to }}D$

1. Methane

2. Alcohol

3. Acetylene

4. Benzaldehyde

Q. The relative order of ease of dehydration of the following alcohols is:
2-Methylpropan-2-ol>Propan-2-ol>Propan-1-ol

1. True
2. False

Q.

Arrange the following alcohols in order of increasing ease of dehydration
$C{H}_{3}C{H}_{2}OH$ $C_6{H}_{5}C{H}_{2}OH$
I II

$C{l}_{3}CC{H}_{2}OH$ $F_{3}CC{H}_{2}OH$
​ III IV

1. II < I < IV < III

2. IV < III < II < I

3. IV < III < I < II

4. II < I < III < IV

Q. Which of the following will be the correct product (P) for the given reaction?

1. 
2. 
3. 
4. 

Q.

The following alcohol is treated with conc. $H_{2}S{O}_4$, the major product obtained is ?

1. 
   

2. 
   

3. 
   

4. All the three will be formed in equal amounts

Q.

The step which is not involved in dehydration of alcohol is:

1. Protonation

2. Elimination of water molecule

3. Formation of carbanion

4. Elimination of proton

Q.

For the above reaction , the major product (A) is :

1. 
2. 
3. 
4. 

Q. Which of the following is not the product of dehydration of the given compound?

1. 
2. 
3. 
4.