Free Alkyl Halides MCQs with Answers
458 Alkyl Halides MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Alkyl halides are named and related to their carbon-halogen structure, polarity and reactivity. The key reactions are nucleophilic substitution by SN1 and SN2 mechanisms and elimination by E1 and E2 mechanisms, including how substrate structure, nucleophile, base, solvent and temperature influence substitution versus elimination.
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Read the Alkyl Halides notesFree MDCAT chapter notes with key terms458 questions · page 10 of 23
- A. From the side of leaving group
- B. Opposite to leaving group
- C. In front of leaving group
- D. Below leaving group
Explanation: This option is correct as in SN2 mechanism the nucleophile attacks on the opposite side to the leaving group since this provides the best…
Correct answer: Opposite to leaving group- A. SN2
- B. E1
- C. SN1
- D. E2
Explanation: Correct Option : DThis option is correct because E2 reactions take place in the presence of non polar solvent and a base.
Correct answer: E2- A. CH3CH2CH2CH2OH
- B. CH3CH2CH2OH
- C. CH3CH2COOH
- D. CH3CH2CH2Br
Explanation: Grignard reagents are highly reactive organomagnesium halides formed by the reaction of magnesium metal with alkyl or alkenyl halides.
Correct answer: CH3CH2COOH- A. From opposite side of leaving group
- B. From front of leaving group
- C. From both sides
- D. None of these
Explanation: During an SN1 mechanism, the nucleophile can attack the halogen carbon from both sides as the intermediate carbocation formed is sp2…
Correct answer: From both sides- A. Nucleophilic elimination reaction
- B. Nucleophilic addition reaction
- C. Nucleophilic substitution reaction
- D. All of these options are correct
Explanation: As indicated by the name, option C is correct The correct option is: "Nucleophilic substitution reaction." In a nucleophilic substitution…
Correct answer: Nucleophilic substitution reaction- A. Alpha-elimination
- B. Gamma-elimination
- C. Beta-elimination
- D. Syn-elimination
Explanation: Beta-elimination, also referred to as β-elimination or 1,2-elimination, is a common type of reaction observed in alkyl halides.
Correct answer: Beta-elimination- A. Solid
- B. Liquid
- C. Gas
- D. All of these options are correct
Explanation: Gas phase favors SN2 reactions while SN1 reactions are uncommon in gas phase.
Correct answer: Gas- A. 2-Chloropropane
- B. 3-Bromobutane
- C. 2,3-Dichloropentane
- D. 2-Chloro-2-methylpentane
Explanation: In this compound, the carbon atom bonded to chlorine is attached to only one other carbon atom (the methyl group).
Correct answer: 2-Chloro-2-methylpentane- A. Chlorobutane
- B. Chloropentane
- C. n-Chloropentane
- D. n-pentyl chloride
- E. 1-chloropentane
Explanation: The open structural formula of the compound is CH3-CH2-CH2-CH2-Cl. Its name is chlorobutane.
Correct answer: Chlorobutane- A. HBr > HI > HCI
- B. HI > HBr > HF
- C. HF>Hl>HCl
- D. HI > HBr > HCl
Explanation: The order of reactivity of alkenes with hydrogen halide decreases down the group, hence option D is the correct answer.
Correct answer: HI > HBr > HCl- A. Hexane-1,5-diamine
- B. Hexane-1,6-diamine
- C. Hexane-1,4-diamine
- D. Hexane-2,5-diamine
Explanation: This compound contains a primary amine group (-NH2) at the 1st and 4th positions of the hexane chain.
Correct answer: Hexane-1,4-diamine- A. A
- B. B
- C. C
- D. D
Explanation: When ethanoic acid reacts with methylamine, it undergoes a condensation reaction to form an amide.
Correct answer: D- A. A
- B. B
- C. C
- D. D
Explanation: The reaction of ethene with bromine is a typical example of electrophilic addition reaction.
Correct answer: A- A. SN1 Mechanism
- B. SN2 Mechanism
- C. Both E1 and E2
- D. Both SN1 and SN2
Explanation: In the case of dihaloalkanes or secondary halogenoalkanes, both SN1 and SN2 mechanisms can occur.
Correct answer: Both SN1 and SN2- A. Elimination
- B. Dehydration
- C. Debromination
- D. Reduction of benzene
Explanation: Halogenoalkanes also undergo elimination reactions in the presence of sodium or potassium hydroxide forming an alkene.
Correct answer: Elimination- A. CH3―CH2―NH―CH2―CH3
- B. CH3―CH2―NH2
- C. CH3―CH2―CH2―NH2
- D. H2N―CH2―CH2―NH2
Explanation: With bromoethane and ammonia, ethyl ammonium bromide is formed as shown below:
Correct answer: CH3―CH2―NH2- A. RI > RBr > RF > RCl
- B. RI > RBr > RCl > RF
- C. RF > RCl > RBr > RI
- D. RF > RBr > RCl > RI
Explanation: The alkyl halides are very reactive due to the highly polarised C - X bond with a large difference in electronegativities of carbon and…
Correct answer: RI > RBr > RCl > RF- A. Reagent for I is KOH in alcohol
- B. Reagent for II is KOH in aqueous medium
- C. Reaction I is Debromination
- D. Reaction II is elimination
Explanation: Elimination of primary alkyl halides gives alkenes, reaction II is KOH in alcohol and reaction I is KOH in aqueous medium.
Correct answer: Reaction II is elimination- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: The formula of proline is C9H5NO2 and its IUPAC name is pyrrolidine-2-carboxylic acid.
Correct answer: Option A200. The mechanism followed by the reaction below is:CH3CH2Br → H2C=CH2 + HBr (Conditions: alcoholic KOH)
- A. E2
- B. E1
- C. SN1
- D. SN2
Explanation: The formation of ethene shows that the reaction is elimination reaction Primary alkyl halides follow the E2 mechanism The alcohol medium…
Correct answer: E2