Quiz for Elimination

Q1: Which of the following reactions is an example of β-elimination?

A. Formation of alkene from bromoethane B. Conversion of alcohol to ether C. Hydrolysis of alkyl halide D. Reaction with Mg to form Grignard reagent

Q2: In E2 mechanism, the rate of reaction depends on:

A. Only substrate concentration B. Only base concentration C. Both substrate and base concentration D. Neither substrate nor base concentration

Q3: Which of the following is the best leaving group for an elimination reaction?

A. F⁻ B. Cl⁻ C. OH⁻ D. TsO⁻

Q4: E1 mechanism involves formation of:

A. Carbanion intermediate B. Carbocation intermediate C. Radical intermediate D. None

Q5: Which compound undergoes E2 reaction most readily?

A. 1-Chlorobutane B. 2-Chlorobutane C. 2-Chloro-2-methylpropane D. Chloromethane

Q6: Which of the following bases favors E2 over SN2?

A. Weak base B. Strong bulky base C. Nucleophile only D. Dilute HCl

Q7: Zaitsev’s rule states that the major product is:

A. Least substituted alkene B. Most substituted alkene C. Primary alkane D. Alkyne

Q8: Hofmann elimination gives:

A. Most substituted alkene B. Least substituted alkene C. No alkene D. Alcohol

Q9: Which is true about E1 and SN1 reactions?

A. Both involve carbocation B. Both are bimolecular C. Both need strong base D. None

Q10: Elimination reactions generally result in the formation of:

A. Alkanes B. Amines C. Alkenes D. Alcohols

Q11: In E2 reaction, the proton and leaving group must be:

A. Cis to each other B. Trans (anti-periplanar) C. On same atom D. On adjacent carbon atoms

Q12: The slow step in E1 reaction is:

A. Loss of proton B. Attack of base C. Formation of carbocation D. Bond rearrangement

Q13: Which of the following favors E1 mechanism?

A. Strong base B. Tertiary halide and weak base C. Primary halide D. Low temperature

Q14: Which type of solvent favors E1?

A. Polar protic B. Polar aprotic C. Non-polar D. Hydrocarbon

Q15: Which of the following is NOT true about E2?

A. Concerted mechanism B. Requires β-H C. Carbocation intermediate forms D. Anti-periplanar geometry is required

Q16: Which product is formed by dehydrohalogenation of 2-bromobutane?

A. 1-butene B. 2-butene C. Butanol D. Butanal

Q17: Which halide undergoes fastest E1?

A. Tertiary B. Secondary C. Primary D. Methyl

Q18: Which of the following does NOT undergo E2 easily?

A. 2-Bromo-2-methylpropane B. 1-Bromobutane C. 2-Bromobutane D. 3-Bromopentane

Q19: Which condition favors E2 over SN2?

A. Strong nucleophile, weak base B. Bulky base, high temperature C. Polar protic solvent D. Low temperature

Q20: How many β-hydrogens are in 2-bromopropane?

A. 1 B. 2 C. 3 D. 6