Explore topic-wise MCQs in Organic Chemistry.

This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Organic Chemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following are incorrect statement?

A. X being electronegative, makes the H (on C-2) more acidic
B. Due to electron withdrawal nature of X, it stabilises the carbanion
C. (X) destabilises the carbanion due to the presence of lone pairs
D. The reaction proceeds by an E1CB pathway
Answer» D. The reaction proceeds by an E1CB pathway
Discussion
2.

Which of the following compounds cannot give E1CB reaction?

A. CF3 – CHCl2
B. C6h5 – CH2 – CH2F
C. CH3 – CH2 – CH2Br
D.
Answer» E.
Discussion
3.

In which reaction product formation takes place by hoffmann rule?

A. I and II
B. II and III
C. I, II and III
D. I, II, III and IV
Answer» E.
Discussion
4.

Which incorrect about alkyl bromide having molecular formula C5H11Br?

A. One isomeric alkyl bromide undergoes E1 elimination at the fastest rate
B. Only one is incapable of reacting by the E2 mechanism
C. Only one isomer gives a single alkene on E2 elimination
D. 2-Bromopentane gives the most complex mixture of alkenes on E2 elimination
Answer» D. 2-Bromopentane gives the most complex mixture of alkenes on E2 elimination
Discussion
5.

Which of the following statement (s) is/are true about the following eliminations?(1) Hoffmann product is major product in I (2) Saytzeff product is major product in I (3) Hoffmann product is major product in II (4) Saytzeffproduct is major product in II

A. 1 and 2
B. 1 and 4
C. 2 and 3
D. 3 and 4
Answer» C. 2 and 3
Discussion
6.

Which of the following statement is correct regarding the following reaction?

A. Major product is endocyclic alkene formed according to Saytzeff
B. Major product is exocyclic alkene formed according to Saytzeff
C. Major product is exocyclic alkene formed according to Hoffmann
D. Major product is endocyclic alkene formed according to Hoffmann
Answer» D. Major product is endocyclic alkene formed according to Hoffmann
Discussion
7.

Which of the following is incorrect statement for the giver reaction?

A. Rate of formation of II and IV would be identical
B. Rate of formation of I would be slower than that of III
C. Formation of I would show primary isotope effect
D. Formation of III involves E1 reaction
Answer» E.
Discussion
8.

Assuming both the reactions as E1, where will the expected ratio between KH/KD lies between?

A. nearly I
B. nearly 3
C. nearly 5
D. anything in between 2 and 8
Answer» B. nearly 3
Discussion
9.

WHICH_INCORRECT_ABOUT_ALKYL_BROMIDE_HAVING_MOLECULAR_FORMULA_C5H11BR??$

A. One isomeric alkyl bromide undergoes E1 elimination at the fastest rate
B. Only one is incapable of reacting by the E2 mechanism
C. Only one isomer gives a single alkene on E2 elimination
D. 2-Bromopentane gives the most complex mixture of alkenes on E2 elimination
Answer» D. 2-Bromopentane gives the most complex mixture of alkenes on E2 elimination
Discussion
10.

Which of the following order is incorrect for the rate of E2 reaction?

A. 5-Bromocycloheptene > 4-Bromocycloheptene
B. 2-Bromo- I -phenylbutane > 3-Bromo- I-phenylbutane
C. 3-Bromocyclohexene > Bromocyclohexane
D. 3-Bromo-2-methylpentane > 2-Bromo-4-methylpentane
Answer» B. 2-Bromo- I -phenylbutane > 3-Bromo- I-phenylbutane
Discussion
11.

Which of the following statements is correct for alkyl halide?

A. Alkyl halide will always show S<sub>N</sub>1 mechanism
B. As branching at carbon increases, E1 mechanism is favoured as compared to S<sub>N</sub>1 mechanism
C. In unimolecular reaction, increasing the temperature donot favours E1 mechanism
D. In most unimolecular reactions of alkyl halide E1 reaction is favoured over SN1 reaction
Answer» C. In unimolecular reaction, increasing the temperature donot favours E1 mechanism
Discussion