Tag: chemical properties of ethers

Questions Related to chemical properties of ethers

Oxygen atom of ether is: 

chemistry hydroxy compounds and ethers chemical properties of ethers ethers alcohols, phenols and ethers

  1. very active

  2. replaceable

  3. active

  4. comparatively inert

Show answer
Correct Option: D
Explanation:
Oxygen atom of ether is comparatively inert.

 $C-O-C$ linkage is quite stable. Under ordinary conditions, ethers are not acted upon by dilute acids, bases and most of the oxidizing and reducing agents. 

Hence correct answer is option D.

$C _2H _5-O-C _2H _5 +  HI \xrightarrow {?}  C _2H _5-OH + C _2H _5-I$
Identify the reaction condition, in which reaction occur.

chemistry hydroxy compounds and ethers chemical properties of ethers ethers alcohols, phenols and ethers

  1. High temperature

  2. High vaccum

  3. Cold

  4. None of the above

Show answer
Correct Option: A
Explanation:

The cleavage of ethers takes places with concentration $HI$ or $HBr$ at high temperature.

Diethyl ether can be decomposed with:

chemistry hydroxy compounds and ethers chemical properties of ethers ethers alcohols, phenols and ethers

  1. $HI$

  2. $KMnO _4$

  3. $NaOH$

  4. $H _2O$

Show answer
Correct Option: A
Explanation:

On heating with concentrated Hydrogen iodide $(HI)$ the C-O bond in ethers breaks forming alcohol and alkyl iodide. For example,

 ${ C } _{ 2 }{ H } _{ 5 }-O-{ C } _{ 2 }{ H } _{ 5 }+HI\longrightarrow { C } _{ 2 }{ H } _{ 5 }-I+{ C } _{ 2 }{ H } _{ 5 }OH$

 On boiling with excess of concentrated Hydrogen iodide $(HI)$, Alkyl iodide is formed.

${ C } _{ 2 }{ H } _{ 5 }-O-{ C } _{ 2 }{ H } _{ 5 }+2HI\longrightarrow 2{ C } _{ 2 }{ H } _{ 5 }-I+{ H } _{ 2 }O$

When an ether is treated with $P _2S _5$, it gives:

chemistry hydroxy compounds and ethers chemical properties of ethers ethers alcohols, phenols and ethers

  1. thioalcohol

  2. thioether

  3. thioester

  4. thioacetal

Show answer
Correct Option: B
Explanation:

When an ether is treated with $P _2S _5$, it gives thioether.


$5C _2H _5-O-C _2H _5+P _2S _5\rightarrow\underset{Thioether}{5C _2H _5-S-C _2H _5}$

Hence option B isthe correct answer.

Ethers are heated with excess of conc. hydrogen halide to give alkyl halide, then the reactivity order of hydrogen halide is :

chemistry hydroxy compounds and ethers chemical properties of ethers ethers alcohols, phenols and ethers

  1. $HCl < HBr < HF$

  2. $HI > HBr > HCl $

  3. $HF < HCl < HBr $

  4. none of these

Show answer
Correct Option: B
Explanation:

When $HX$ is in excess and reaction is carried out at high temperature. Iodine is a good nucleophile, displaces an alcohol molecule by $SN^2$ mechanism thus $HI>HBr>HCl$

Ethyl phenyl ether on boiling with conc. HBr gives: 

chemistry hydroxy compounds and ethers chemical properties of ethers ethers alcohols, phenols and ethers

  1. phenol and ethane

  2. bromobenzene and ethane

  3. phenol and ethyl bromide

  4. bromobenzene and ethanol

Show answer
Correct Option: A