This is third assignment for Aromaticity and General Organic Chemistry.
Aromaticity MCQ Questions - Assignment 3
Q1. The correct statement about the following is
a) I and II are resonating structures
b) I and II have 4 sp2 atoms
c) I and II are different compounds
d) I has 4 sp2 atoms and II has 6 sp2 atoms
Q2. Which of the following is/are stable hydrate (s)?
a) III only
b) II and III
c) I, II and III
d) all of these
Q3. Order of stability for the following carbocations follows:
a) I<III<II<IV
b) I<III<II=IV
c) I<II=IV<III
d) I<II=III=IV
Q4. The following molecule follows carbocationic mechanism. The decreasing order of the positions for preferential reaction is:
a) 2 > 1 > 3
b) 1 > 2 > 3
c) 2 > 3 > 1
d) 1 > 3 > 2
Q5. Match the following carbanions with their corresponding half-lives
a) (A-R), (B-S), (C-Q), (D-P)
b) (A-R), (B-Q), (C-S), (D-P)
c) (A-S), (B-Q), (C-P), (D-R)
d) (A-Q), (B-S), (C-P), (D-R)
Q6. For which of the following reactions, the equilibrium constant (K) is less than unity?
a) 
b) 
c) 
d) 
Q7. Selected bond angles for six hydrocarbons are shown below. Arrange these hydrocarbons according to their pKa values, from the lowest to the highest.
a) 
b) 
c) 
d) 
Q8. Which of the following is the correct order of basic nature?
a) Q > R > P
b) R > Q > P
c) R > P > Q
d) Q > P > R
Q9. Arrange the following compounds, in decreasing order of C-N bond length:
a) D > C > B > A
b) D > C > A > B
c) A > B > C > D
d) D > A > C > B
Q10. Molecular orbital interactions involved in the first step of the following reaction is:
Q11. Which of the following compound is best hydride donor?
a) 
b) 
c) 
d) 
Q12. How many of the following compounds are not aromatic?
a) 1
b) 2
c) 3
d) 4
Q13. In which of the following pairs, the resonance energy of second compound is higher than the first?
a) 
b) 
c) 
d) 
Q14. Compound which is least reactive towards LiAlH4?
Q15. Which of the following compounds are aromatic?
a) I and II
b) I, II and IV
c) I, II, III, IV
d) Only I and IV
Q16. The value of ‘n’ for the following molecule according to Huckel’s rules is:
a) 7
b) 16
c) 14
d) 3
Q17. Among the following, which is correct?
a) Both cyclopentadienyl anion and benzene are aromatic and have the same stability
b) Benzene is aromatic and more stable than cyclopentadienyl anion which is anti-aromatic
c) Both are aromatic, but benzene is more stable than cyclopentadienyl anion
d) Cyclopentadienyl anion is more stable than benzene although both are aromatic
Q18. Correct order towards Diels-Alder reaction:
a) III > II > I > IV
b) III > IV > I > II
c) III > I > II > IV
d) II > I > III > IV
Q19. Correct order of acidity of the following acids:
a) D > A > B > C
b) B > D > C > A
c) C > A > B > D
d) C > B > D > A
Q20. Total no. of anti-aromatic compounds are:
a) 1
b) 2
c) 3
d) 4
Answer Key
1-c, 2-c, 3-b, 4-b, 5-a, 6-d, 7-d, 8-b, 9-b, 10-c, 11-b, 12-b, 13-b, 14-c, 15-b, 16-d, 17-c, 18-c, 19-d, 20-b