Questions on Alkyl Halides (Organic Chemistry).
20 multiple-choice questions with five alternatives (A–E) on Alkyl Halides (Organic Chemistry). The correct answers and extended explanations are provided at the end.
-- Ads --
Multiple Choice Questions: Alkyl Halides (Organic Chemistry)
1. What is the general formula for an alkyl halide?
A) R–OH
B) R–COOH
C) R–X
D) R–NH₂
E) R–CHO
2. In alkyl halides, what does "X" represent?
A) Any metal
B) Oxygen or sulfur
C) Hydrogen
D) A halogen atom (F, Cl, Br, I)
E) A hydroxide ion
3. What is the IUPAC name of CH₃CH₂Cl?
A) Chloroethane
B) Ethyl chloride
C) Methyl chloride
D) Dichloroethane
E) Ethanol
4. Which of the following is a primary alkyl halide?
A) CH₃CHClCH₃
B) CH₃CH₂CH₂Cl
C) CH₃CCl₃
D) CCl₄
E) CH₃CH₂CH₂Br
5. Which of the following is a tertiary alkyl halide?
A) CH₃CH₂Cl
B) (CH₃)₃CCl
C) CH₃CH₂CH₂Br
D) CH₃CH₂CH₂I
E) CH₃CHClCH₂CH₃
6. Which hybridization does the carbon bonded to the halogen usually have in alkyl halides?
A) sp
B) sp²
C) sp³
D) dsp²
E) sp³d
7. Which of the following solvents would best promote an SN1 reaction in alkyl halides?
A) Hexane
B) Benzene
C) Water
D) Cyclohexane
E) Ether
8. What type of mechanism involves a carbocation intermediate?
A) SN2
B) E2
C) E1
D) SN1
E) Free radical substitution
9. Which of the following alkyl halides is most reactive in SN1 reactions?
A) Methyl chloride
B) Ethyl chloride
C) Isopropyl bromide
D) tert-Butyl bromide
E) Vinyl chloride
10. In an SN2 reaction, the reaction rate depends on:
A) Only the alkyl halide
B) Only the nucleophile
C) Temperature only
D) Both nucleophile and alkyl halide
E) Catalyst concentration
11. Which halide is the best leaving group?
A) F⁻
B) Cl⁻
C) Br⁻
D) I⁻
E) OH⁻
12. What is the major product when CH₃CH₂Br reacts with aqueous NaOH?
A) Ethene
B) Ethanol
C) Ethanal
D) Methanol
E) Acetic acid
13. What kind of reaction is it when an alkyl halide reacts with a nucleophile?
A) Elimination
B) Substitution
C) Polymerization
D) Combustion
E) Condensation
14. What is the hybridization of the carbon in methyl chloride (CH₃Cl)?
A) sp
B) sp²
C) sp³
D) sp³d
E) sp²d
15. What happens to the boiling point of alkyl halides with increasing molecular weight?
A) Decreases
B) Increases
C) Remains constant
D) First increases then decreases
E) Not predictable
16. Which factor does NOT affect SN1 reactivity?
A) Carbocation stability
B) Nature of the leaving group
C) Concentration of nucleophile
D) Solvent polarity
E) Structure of alkyl halide
17. What is formed when a tertiary alkyl halide undergoes elimination (E1)?
A) Ether
B) Alkene
C) Alcohol
D) Ester
E) Halohydrin
18. Which statement is true about alkyl halides?
A) They are nonpolar
B) They have low boiling points
C) They are highly reactive due to the electronegative halogen
D) They are soluble in water
E) They contain nitrogen
19. What type of bond is formed between carbon and halogen in alkyl halides?
A) Ionic bond
B) Hydrogen bond
C) Covalent polar bond
D) Nonpolar covalent bond
E) Coordinate bond
20. Which of the following is NOT an application of alkyl halides?
A) Solvent in organic reactions
B) Production of refrigerants
C) Fuel additive
D) DNA replication
E) Anesthetic production
- Questions about Carboxylic Acids (Organic Chemistry)
- Questions about Esters (Organic Chemistry)
- Questions on Amines (Organic Chemistry)
✅ Answer Key with Extended Explanations
1. C – Alkyl halides have the general formula R–X, where X is a halogen.
2. D – In alkyl halides, X represents halogens: F, Cl, Br, or I.
3. A – CH₃CH₂Cl is named chloroethane in IUPAC.
4. B – CH₃CH₂CH₂Cl is a primary alkyl halide; the halogen is attached to a primary carbon.
5. B – (CH₃)₃CCl is tertiary; the carbon bearing the halogen is bonded to three other carbon atoms.
6. C – The carbon in alkyl halides is sp³ hybridized.
7. C – Water is a polar protic solvent that stabilizes carbocations, favoring SN1.
8. D – SN1 reactions involve a carbocation intermediate.
9. D – tert-Butyl bromide forms the most stable carbocation, making it ideal for SN1.
10. D – SN2 reactions are bimolecular, depending on both nucleophile and alkyl halide.
11. D – Iodide (I⁻) is the best leaving group due to its size and low basicity.
12. B – CH₃CH₂Br + NaOH → CH₃CH₂OH (ethanol) in substitution.
13. B – Reaction of an alkyl halide with a nucleophile is a nucleophilic substitution.
14. C – Carbon in CH₃Cl is sp³ hybridized.
15. B – Boiling points increase with molecular weight due to greater van der Waals forces.
16. C – In SN1, nucleophile strength is not critical, as it's a two-step reaction.
17. B – E1 reactions on tertiary halides form alkenes.
18. C – Alkyl halides are reactive due to the polar C–X bond.
19. C – The C–X bond is polar covalent due to electronegativity difference.
20. D – Alkyl halides are not involved in DNA replication.
Dive into the groundbreaking science of neurotransmitters—your brain’s invisible architects—in Chemical Harmony: How Neurotransmitters Shape Our Lives (2025). This meticulously researched book reveals how serotonin, dopamine, GABA, and other brain chemicals silently orchestrate every aspect of your existence, from decision-making and relationships to mental health and emotional resilience.Click here to buy
Share Online!
