NEET > Hydrocarbons

Explore popular questions from Hydrocarbons for NEET. This collection covers Hydrocarbons previous year NEET questions hand picked by popular teachers.


Q 1.    

Correct4

Incorrect-1

Which one is the correct order of acidity?

{tex}\mathrm {CH\equiv CH>CH_3-C\equiv CH>CH_2=CH_2>CH_3-CH_3}{/tex}

B

{tex}\mathrm {CH\equiv CH>CH_2=CH_2 >CH_3-C\equiv CH>CH_3-CH_3}{/tex}

C

{tex}\mathrm {CH_3-CH_3>CH_2=CH_2>CH_3-C\equiv CH>CH\equiv CH }{/tex}

D

{tex}\mathrm {CH_2=CH_2>CH_3-CH=CH_2>CH_3-C\equiv CH>CH\equiv CH }{/tex}

Explanation

Q 2.    

Correct4

Incorrect-1

Predict the correct intermediate and product in the following reaction :

A

B

D

Explanation

Q 3.    

Correct4

Incorrect-1

With respect to the conformers of ethane, which of the following statements is true?

A

Bond angle changes but bond length remains same.

B

Both bond angle and bond length change.

Both bond angle and bond length remain same.

D

Bond angle remains same but bond length changes.

Explanation

Q 4.    

Correct4

Incorrect-1

Which of the following can be used as the halide component for Friedel-Crafts reaction?

A

Chlorobenzene

B

Bromobenzene

C

Chloroethene

Isopropyl chloride

Explanation

Q 5.    

Correct4

Incorrect-1

In which of the following molecules, all atoms are coplanar?

B

C

D

Explanation

Q 6.    

Correct4

Incorrect-1

In pyrrole the electron density is maximum on

A

2 and 3

B

3 and 4

C

2 and 4

2 and 5

Explanation



Q 7.    

Correct4

Incorrect-1

Which of the following compounds shall not produce propene by reaction with HBr followed by elimination or direct only elimination reaction?

A

B

D

Explanation

Q 8.    

Correct4

Incorrect-1

In the given reaction,

the product P is

A

B

D

Explanation

Q 9.    

Correct4

Incorrect-1

The compound that will react most readily with gaseous bromine has the formula

{tex} \mathrm { C } _ { 3 } \mathrm { H } _ { 6 } {/tex}

B

{tex} \mathrm { C_2 } \mathrm { H_2 } {/tex}

C

{tex} \mathrm { C } _ { 4 } \mathrm { H } _ { 10 } {/tex}

D

{tex} \mathrm { C } _ { 2 } \mathrm { H } _ { 4 } {/tex}

Explanation

Q 10.    

Correct4

Incorrect-1

The correct statement regarding the comparison of staggered and eclipsed conformations of ethane, is

A

the eclipsed conformation of ethane is more stable than staggered conformation even though the eclipsed conformation has torsional strain

the staggered conformation of ethane is more stable than eclipsed conformation, because staggered conformation has no torsional strain

C

the staggered conformation of ethane is less stable than eclipsed conformation, because staggered conformation has torsional strain

D

the eclipsed conformation of ethane is more stable than staggered conformation, because eclipsed conformation has no torsional strain.

Explanation

Q 11.    

Correct4

Incorrect-1

Consider the nitration of benzene using mixed conc.{tex} \mathrm { H } _ { 2 } \mathrm { SO } _ { 4 } {/tex} and {tex} \mathrm { HNO } _ { 3 } {/tex}. If a large amount of {tex} \mathrm { KHSO } _ { 4 } {/tex} is added to the mixture, the rate of nitration will be

A

unchanged

B

doubled

C

faster

slower

Explanation

Q 12.    

Correct4

Incorrect-1

The pair of electrons in the given carbanion,{tex} \mathrm { CH } _ { 3 } \mathrm { C } \equiv \mathrm { C } ^ { - } , {/tex} is present in which of the following orbitals?

A

{tex} s p ^ { 2 } {/tex}

{tex} s p {/tex}

C

2{tex} p {/tex}

D

{tex} s p ^ { 3 } {/tex}

Explanation

Q 13.    

Correct4

Incorrect-1

In the reaction

X and Y are

A

{tex} X = 2{/tex}-Butyne, {tex} Y = 2{/tex}-Hexyne

B

{tex} X = 1 -{/tex}Butyne {tex} , Y = 2 {/tex}-Hexyne

{tex} X = 1{/tex}-Butyne, {tex} Y = 3{/tex}-Hexyne

D

{tex} X = 2-{/tex}Butyne {tex} , Y = 3{/tex}-Hexyne.

Explanation

Q 14.    

Correct4

Incorrect-1

In the reaction with {tex} \mathrm { HCl } {/tex} , an alkene reacts in accordance with the Markovnikov's rule to give a product 1-chloro-1 methylcyclohexane. The possible alkene is

A

B

{tex} ( A ) {/tex} and {tex} ( B ) {/tex}

D

Explanation

Q 15.    

Correct4

Incorrect-1

{tex} 2,3{/tex}-Dimethyl-2-butene can be prepared by heating which of the following compounds with a strong acid?

{tex} \left( \mathrm { CH } _ { 3 } \right) _ { 3 } \mathrm { CCH } = \mathrm { CH } _ { 2 } {/tex}

B

{tex} \left( \mathrm { CH } _ { 3 } \right) _ { 2 } \mathrm { C } = \mathrm { CHCH } _ { 2 } \mathrm { CH } _ { 3 } {/tex}

C

{tex} \left( \mathrm { CH } _ { 3 } \right) _ { 2 } \mathrm { CHCH } _ { 2 } \mathrm { CH } = \mathrm { CH } _ { 2 } {/tex}

D

Explanation

Q 16.    

Correct4

Incorrect-1

A single compound of the structure,

is obtainable from ozonolysis of which of the following cyclic compounds?

A

B

D

Explanation

Q 17.    

Correct4

Incorrect-1

Given:

The enthalpy of hydrogenation of these compounds will be in the order as

A

{tex} \mathrm { II } > \mathrm { III } > \mathrm { I } {/tex}

B

{tex} \mathrm { II } > \mathrm { I } > \mathrm { III } {/tex}

C

{tex} \mathrm { I } > \mathrm { II } > \mathrm { III } {/tex}

{tex} \mathrm { III } > \mathrm { II } > \mathrm { I } {/tex}

Explanation

Q 18.    

Correct4

Incorrect-1

What products are formed when the following compound is treated with {tex} \mathrm { Br } _ { 2 } {/tex} in the presence of {tex} \mathrm { FeBr } _ { 3 } ? {/tex}

A

B

D

Explanation


Q 19.    

Correct4

Incorrect-1

Identify Z in the sequence of reactions :

{tex} \mathrm { CH_3-(CH } _ { 2 } ) _ { 3 } - \mathrm { O } - \mathrm { CH } _ { 2 } \mathrm { CH } _ { 3 } {/tex}

B

{tex} \left( \mathrm { CH } _ { 3 } \right) _ { 2 } \mathrm { CH } - \mathrm { O } - \mathrm { CH } _ { 2 } \mathrm { CH } _ { 3 } {/tex}

C

{tex} \mathrm { CH } _ { 3 } \left( \mathrm { CH } _ { 2 } \right) _ { 4 } - \mathrm { O } - \mathrm { CH } _ { 3 }{/tex}

D

{tex} \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } - \mathrm { CH } \left( \mathrm { CH } _ { 3 } \right) - \mathrm { O } - \mathrm { CH } _ { 2 } \mathrm { CH } _ { 3 } {/tex}

Explanation

Q 20.    

Correct4

Incorrect-1

Which of the following organic compounds has same hybridization as its combustion product {tex} \left( \mathrm { CO } _ { 2 } \right) ? {/tex}

A

Ethane

Ethyne

C

Ethene

D

Ethanol

Explanation

Q 21.    

Correct4

Incorrect-1

Which of the following compounds will not undergo Friedal-Craft's reaction easily?

Nitrobenzene

B

Toluene

C

Cumene

D

Xylene

Explanation

Q 22.    

Correct4

Incorrect-1

Which of the following chemical system is non aromatic?

A

B

C

Explanation

Q 23.    

Correct4

Incorrect-1

In the following reaction:

Product 'P' will not give

A

Tollen's reagent test

B

Brady's reagent test

Victor Meyer test

D

Iodoform test

Explanation

Q 24.    

Correct4

Incorrect-1

In the following reaction

The major product is

B

C

D

Explanation

Q 25.    

Correct4

Incorrect-1

Which of the following acids does not exhibit optical isomerism?

Maleic acid

B

{tex}\alpha {/tex}-amino acids

C

Lactic acid

D

Tartaric acid

Explanation