Class 12 Chemistry MCQ Chapter 6 Haloalkanes and Haloarenes
Preparing for your AHSEC board examinations? Our Class 12 Chemistry MCQ Chapter 6 Haloalkanes and Haloarenes English Medium resource is designed to help students master the chapter through carefully selected multiple-choice questions and detailed solutions.
This chapter focuses on the structure, nomenclature, preparation methods, physical properties, and chemical reactions of Haloalkanes and Haloarenes. Students will also learn about nucleophilic substitution reactions, elimination reactions, environmental effects of halogen compounds, and the practical applications of these important organic compounds. The MCQs included here are based on the latest AHSEC syllabus and examination pattern, making them highly useful for board exam preparation.
Each question comes with the correct answer to help students evaluate their understanding, identify weak areas, and improve their problem-solving skills. Regular practice of these objective questions can significantly enhance accuracy, speed, and confidence before examinations.
Whether you are revising the chapter for the first time or completing your final exam preparation, these MCQ solutions will serve as a reliable and effective study companion for achieving better results in Chemistry.
Part II
Haloalkanes and Haloarenes
VSA & MCQ
I. Short Question-Answer
Q. What are haloalkanes?
Ans: Organic compounds in which halogen atom is attached to an alkyl group.
Q. What are haloarenes?
Ans: Compounds in which halogen is directly attached to an aromatic ring.
Q. What is general formula of haloalkanes?
Ans: R–X (where X = F, Cl, Br, I)
Q. What is C–X bond nature?
Ans: Polar covalent bond.
Q. Order of bond strength of C–X bond.
Ans: C–F > C–Cl > C–Br > C–I
Q. What is nucleophile?
Ans: Electron-rich species that attacks electron-deficient centre.
Q. What is electrophile?
Ans: Electron-deficient species.
Q. What is SN1 reaction?
Ans: Unimolecular nucleophilic substitution.
Q. What is SN2 reaction?
Ans: Bimolecular nucleophilic substitution.
Q. Order of reactivity in SN1 reaction.
Ans: 3° > 2° > 1°
Q. Order of reactivity in SN2 reaction.
Ans: 1° > 2° > 3°
Q. What is carbocation?
Ans: Positively charged carbon species.
Q. What is elimination reaction?
Ans: Removal of atoms to form double bond.
Q. What is E1 reaction?
Ans: Unimolecular elimination.
Q. What is E2 reaction?
Ans: Bimolecular elimination.
Q. Why haloarenes are less reactive?
Ans: Due to resonance and partial double bond character.
Q. What is resonance in haloarenes?
Ans: Delocalisation of electrons in aromatic ring.
Q. What is benzyl halide?
Ans: Halogen attached to benzylic carbon.
Q. What is allyl halide?
Ans: Halogen attached to allylic carbon.
Q. What is Wurtz reaction?
Ans: Coupling of alkyl halides using Na in dry ether.
Q. Write Wurtz reaction.
Ans: 2R–X + 2Na → R–R + 2NaX
Q. What is Finkelstein reaction?
Ans: Halogen exchange reaction using NaI.
Q. What is Swarts reaction?
Ans: Conversion of alkyl chloride/bromide to fluoride.
Q. What is Grignard reagent?
Ans: RMgX, formed by reaction with Mg in dry ether.
Q. What is SN1 mechanism rate dependence?
Ans: Rate = k[R–X]
Q. What is SN2 mechanism rate dependence?
Ans: Rate = k[R–X][Nu⁻]
Q. What is optical activity?
Ans: Rotation of plane polarized light.
Q. What is racemic mixture?
Ans: Equal mixture of enantiomers.
Q. What is inversion of configuration?
Ans: Change in spatial arrangement.
II. Multiple Choice Questions (MCQs)
Q. Haloalkanes contain:
(a) C–H
(b) C–X
(c) C–O
(d) C–N
Ans: (b)
Q. Most reactive in SN1:
(a) 1°
(b) 2°
(c) 3°
(d) CH₃
Ans: (c)
Q. Most reactive in SN2:
(a) 3°
(b) 2°
(c) 1°
(d) Benzyl
Ans: (c)
Q. SN1 mechanism forms:
(a) Radical
(b) Carbocation
(c) Carbanion
(d) Ion pair
Ans: (b)
Q. SN2 mechanism is:
(a) One step
(b) Two step
(c) Three step
(d) No step
Ans: (a)
Q. Haloarenes are less reactive due to:
(a) Inductive effect
(b) Resonance
(c) Size
(d) Shape
Ans: (b)
Q. Wurtz reaction forms:
(a) Alkene
(b) Alkane
(c) Alcohol
(d) Ether
Ans: (b
Q. Grignard reagent is:
(a) RMgX
(b) RNa
(c) RX
(d) RCl
Ans: (a)
Q. Finkelstein reaction involves:
(a) Fluorine
(b) Chlorine
(c) Iodine
(d) Bromine
Ans: (c)
Q. Swarts reaction forms:
(a) Alkyl fluoride
(b) Alkyl chloride
(c) Alkyl bromide
(d) Alkyl iodide
Ans: (a)
Q. Carbocation stability order:
(a) 1° > 2° > 3°
(b) 3° > 2° > 1°
(c) 2° > 3° > 1°
(d) Equal
Ans: (b)
Q. SN2 reaction shows:
(a) Retention
(b) Inversion
(c) No change
(d) Racemization
Ans: (b)
Q. Allyl halides are:
(a) Stable
(b) Unstable
(c) Reactive
(d) Neutral
Ans: (c)
Q. Assertion: SN1 reaction forms carbocation.
Reason: Bond breaks heterolytically.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (b)
Q. Assertion: SN2 reaction is one-step.
Reason: No intermediate formed.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (d)
Q. Assertion: Haloarenes are less reactive.
Reason: C–X bond has partial double character.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (c)
Q. Assertion: SN2 shows inversion.
Reason: Backside attack occurs.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (a)
Q. Assertion: Wurtz reaction forms alkanes.
Reason: Coupling of alkyl groups.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (b)
Q. Assertion: Grignard reagents are reactive.
Reason: Polar C–Mg bond.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (d)
Q. Assertion: SN1 gives racemic mixture.
Reason: Planar carbocation intermediate.
(a) Both true, R correct explanation
(b) Both true, R not correct explanation
(c) A true, R false
(d) A false, R true
Ans: (c)
