JEE Main PYQs on Isomerism: JEE Main Questions for Practice with Solutions

1.

The number of isomeric forms that are represented by C7H9N is:

• 5
• 2
• 6
• 9

2.

Given below are two statements: 

Statement (I):
  are isomeric compounds. 

Statement (II): 
are functional group isomers.

In the light of the above statements, choose the correct answer from the options given below:

• Both Statement I and Statement II are true
  
• Statement I is false but Statement II is true
  
• Statement I is true but Statement II is false
  
• Both Statement I and Statement II are false
  

3.

Given below are two statements: Statement (I):

are isomeric compounds.
Statement (II):

are functional group isomers.
In the light of the above statements, choose the correct answer from the options given below:

• Both Statement I and Statement II are true
  
• Statement I is false but Statement II is true
  
• Statement I is true but Statement II is false
  
• Both Statement I and Statement II are false
  

4.

The one giving maximum number of isomeric alkenes on dehydrohalogenation reaction is
(excluding rearrangement)

• 2-Bromopropane
• 2-Bromo-3,3-dimethylpentane
• 1-Bromo-2-methylbutane
• 2-Bromopentane

5.

Which one of the following will show geometrical isomerism?

6.

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Cis form of alkene is found to be more polar than the trans form
Reason (R): Dipole moment of trans isomer of 2-butene is zero. In the light of the above statements.
Choose the correct answer from the options given below :

• Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
• (A) is true but (R) is false
• Both (A) and (R) are true and (R) is the correct explanation of (A)
• (A) is false but (R) is true

7.

• Piperidine>Pyridine>Pyrrole
• Pyrrole>Pyridine>Piperidine
• Pyridine>Piperidine>Pyrrole
• Pyrrole>Piperidine >Pyridine

8.

The incorrect statements regarding geometrical isomerism are: 
(A) Propene shows geometrical isomerism. 
(B) Trans isomer has identical atoms/groups on the opposite sides of the double bond. 
(C) Cis-but-2-ene has higher dipole moment than trans-but-2-ene. 
(D) 2-methylbut-2-ene shows two geometrical isomers. 
(E) Trans-isomer has lower melting point than cis isomer. 
 

• (A), (D) and (E) only
  
• (C), (D) and (E) only
  
• (B) and (C) only
  
• (A) and (E) only

9.

Match List - I with List - II.

List - I (Pair of Compounds)	List - II (Isomerism)
(A) n-propanol and Isopropanol	(I) Metamerism
(B) Methoxypropane and ethoxyethane	(IV) Functional Isomerism
(C) Propanone and propanal	(III) Position Isomerism
(D) Neopentane and Isopentane	(II) Chain Isomerism

• (A)–(II), (B)–(I), (C)–(IV), (D)–(III)
• (A)–(III), (B)–(I), (C)–(II), (D)–(IV)
• (A)–(I), (B)–(III), (C)–(IV), (D)–(II)
• (A)–(III), (B)–(I), (C)–(IV), (D)–(II)

10.

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): The total number of geometrical isomers shown by [Co(en)$_2$Cl$_2$]$^+$ complex ion is three.
Reason (R): [Co(en)$_2$Cl$_2$]$^+$ complex ion has an octahedral geometry.
In the light of the above statements, choose the most appropriate answer from the options given below:

• Both (A) and (R) are correct and (R) is the correct explanation of (A).
• (A) is correct but (R) is not correct.
• (A) is not correct but (R) is correct.
• Both (A) and (R) are correct but (R) is not the correct explanation of (A).