Tag: carbon compounds

Questions Related to carbon compounds

Which of the following product is obtained during reaction of ethanoic acid with diazomethane in presence of $dil. HCl$?

  1. Methyl acetate

  2. Ethyl acetate

  3. Methyl formate

  4. Ethyl formate


Correct Option: A
Explanation:

Methyl acetate is obtained during reaction of ethanoic acid with diazomethane in presence of dil HCl.
$CH _3COOH + CH _2N _2 \xrightarrow {dil HCl} CH _3COOCH _3 + N _2$

Which of the following product(s) is$/$are obtained during the reaction of ethanoic acid with chlorine?

  1. Monochloroacetic acid

  2. Dichloroacetic acid

  3. Trichloroacetic acid

  4. All of the above


Correct Option: D
Explanation:

When ethanoic acid reacts with chlorine in the presence of acetic anhydride as catalyst it forms chloroacetic acid.

$CH _3COOH  + Cl _2 \rightarrow ClCH _2COOH + HCl$

Ethanol reacts with sodium and forms two products. These are:

  1. sodium ethanoate and hydrogen

  2. sodium ethanoate and oxygen

  3. sodium ethoxide and hydrogen

  4. sodium ethoxide and oxygen


Correct Option: C
Explanation:

The equation for the reaction between sodium and ethanol can be written as:
$2CH _{3}CH _{2}OH + 2Na \rightarrow 2CH _{3}CH _{2}ONa + H _{2}$
Therefore, the products formed are sodium ethoxide and hydrogen.

Write the type of reaction.
Ethanol is warmed with ethanoic acid to form ethyl acetate in the presence of concentrated $H _{2}SO _{4}.$

  1. Esterification reaction

  2. Neutralisation reaction

  3. Decomposition reaction

  4. Double displacement reaction


Correct Option: A
Explanation:

Reaction of ethanol with warm ethanoic acid to form ethyl acetate(an ester) and water can be written as:
$ C _{2}H _{5}OH +  CH _{3}COOH  \overset{H^{+}}{\rightarrow}   CH _{3}COOC _{2}H _{5}  +  H _{2}O$
(ethanol)      (ethanoic acid)             (ester)
Above reaction is an esterification reaction as an alcohol and an acid are combined to formed an ester. 

Which of the following represents saponification reaction?

  1. $CH _{3}COONa + NaOH \xrightarrow{CaO} CH _{4} + Na _{2}CO _{3}$

  2. $CH _{3}COOH + C _{2}H _{5}OH \xrightarrow{H _{2}SO _{4}} CH _{3} COOC _{2}H _{5} +H _{2}O$

  3. $2CH _{3}COOH + 2Na \rightarrow 2CH _{3} COONa + H _{2}$

  4. $CH _{3}COOC _{2}H _{5} + NaOH \rightarrow CH _{3} COONa + C _{2} H _{5}OH$


Correct Option: D
Explanation:

Saponification is the alkaline hydrolysis of esters to form soap and alcohol. Therefore, the correct answer is option D.

$CH _{3}COOC _{2}H _{5} + NaOH \rightarrow CH _{3}COONa + C _{2}H _{5}OH$
    Ester                         Alkali                Soap               Alcohol

Explain the given reactions with the examples.
Oxidation reaction :

  1. ${ C } _{ 2 }{ H } _{ 5 }OH\xrightarrow { Alk.KMn{ O } _{ 4 } } { C }{ H } _{ 2 }OH{ COOH }$

  2. ${ C } _{ 2 }{ H } _{ 5 }OH\xrightarrow { Alk.KMn{ O } _{ 4 } } { C }{ H } _{ 3 }{ CH _3 }$

  3. ${ C } _{ 2 }{ H } _{ 5 }OH\xrightarrow { Alk.KMn{ O } _{ 4 } } { C }{ H } _{ 3 }{ CH _2OH }$

  4. ${ C } _{ 2 }{ H } _{ 5 }OH\xrightarrow { Alk.KMn{ O } _{ 4 } } { C }{ H } _{ 3 }{ COOH }$


Correct Option: D
Explanation:

Ethanol is oxidised to ethanoic acid in the presence of alkaline
$KMnO _{4}$ on heating
$CH _{3}  CH _{2}  OH \xrightarrow[Heat]{Alk.  KMnO _{4}} CH _{3}COOH$

An organic compound 'A' produces a gas with brisk effervescence when sodium bicarbonate is added to it. The compound 'A' contains same number of carbons as in ethane. The compound 'A' reacts with ethanol to form a sweet smelling compound 'C' in presence of conc. $H _2SO _4$. A and C respectively are :

  1. ethanoic acid and ethyl ethanoate

  2. methanoic acid and ethyl methanoate

  3. ethanoic acid and sodium ethanoate

  4. methanoic acid and sodium methanoate


Correct Option: A
Explanation:

Ethanoic acid reacts with sodium bicarbonate, to form carbon dioxide which produces effervescence as: 


$CH _{3}COOH + NaHCO _{3} \rightarrow CH _{3}COONa + H _{2}O + CO _{2}$ 

Also, ethanoic acid reacts with ethanol to form the ester - ethyl ethanoate as follows: 


$CH _{3}COOH + C _{2}H _{5}OH \overset{conc.\ H _{2}SO _{4}}{\longrightarrow} CH _{3}COOCH _{2}CH _{3} + H _2O$ 

Thus, A is ethanoic acid and C is ethyl ethanoate.

Which of the following is a property of ethanol?

  1. Ionic compound

  2. Noble gas

  3. Polar covalent compound

  4. Nonpolar covalent compound

  5. Metallic substance


Correct Option: C
Explanation:

$C _2H _5OH$ has polar covalent $C-O$ bond due to significant electronegativity difference between $C$ and$ O.$ Similarly $O-H$ bond is also polar covalent due to significant electronegativity difference between $O$ and $H$ atoms.
A covalent bond is formed by sharing of electrons. When this electron sharing is to an equal extent, the bond is non polar covalent. Otherwise the bond is polar covalent.

Name the process for ethanol to ethene conversion and reactants used.
  1. hydrogenation of ethanol in the presence of concentrated $H _{2}SO _{4}.$

  2. dehydration of ethanol in the presence of concentrated $H _{2}SO _{4}.$

  3. oxidation of ethanol in the presence of concentrated $H _{2}SO _{4}.$

  4. reduction of ethanol in the presence of concentrated $H _{2}SO _{4}.$


Correct Option: B
Explanation:

Ethanol can be converted to ethene as:

    $CH _{3}CH _{2}OH \xrightarrow[hot]{conc.H _{2}SO _{4}} CH _{2}= CH _{2} + H _{2}O$

In above reaction, dehydration of ethanol takes place in the presence of concentrated sulphuric acid.
Hence, the correct option is B.

Carbon forms bonds with another element by :

  1. transferring of electrons.

  2. sharing of electrons.

  3. Both A and B.

  4. None of the above.


Correct Option: B
Explanation:

Carbon shares electrons while making compounds. It do not transfers electrons to other ions.


Hence, the correct option is $B$.