Q40.Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Treatment of bromine water with propene yields 1-bromopropan-2-ol. Reason (R) : Attack of water on bromonium ion follows Markovnikov rule and results in 1-bromopropan-2-ol. In the light of the above statements, choose the most appropriate answer from the options given below : (1) Both (A) and (R) are true but (R) is NOT the correct explanation of (A). (2) (A) is false but (R) is true. (3) Both (A) and (R) are true and (R) is the correct explanation of (A ). (4) (A) is true but (R) is false.
What This Question Tests
This question assesses the mechanism and regioselectivity of the addition of bromine water (HOBr) to an alkene, specifically involving the bromonium ion intermediate and nucleophilic attack following Markovnikov's rule.
Concepts Tested
📚 NCERT Sections This Tests
7.17 — Give Equations Of The Following Reactions:
Chemistry Class 12 · Chapter 7
7.17 Give equations of the following reactions: (i) Oxidation of propan-1-ol with alkaline KMnO4 solution. (ii) Bromine in CS2 with phenol. (iii) Dilute HNO3 with phenol. (iv) Treating phenol wih chloroform in presence of aqueous NaOH.
7.13 — Show How Will You Synthesise:
Chemistry Class 12 · Chapter 7
7.13 Show how will you synthesise: (i) 1-phenylethanol from a suitable alkene. (ii) cyclohexylmethanol using an alkyl halide by an SN2 reaction. (iii) pentan-1-ol using a suitable alkyl halide?
7.21 — Name The Reagents Used In The Following Reactions:
Chemistry Class 12 · Chapter 7
7.21 Name the reagents used in the following reactions: (i) Oxidation of a primary alcohol to carboxylic acid. (ii) Oxidation of a primary alcohol to aldehyde. (iii) Bromination of phenol to 2,4,6-tribromophenol. (iv) Benzyl alcohol to benzoic acid. (v) Dehydration of propan-2-ol to propene. (vi) Butan-2-one to butan-2-ol.
📋 Question Details
- Chapter
- Hydrocarbons
- Topic
- Electrophilic addition of HBr/H2O to alkenes
- Year
- 2021
- Shift
- 31 Aug Shift 1
- Q Number
- Q40
- Type
- Assertion Reasoning
- NCERT Ref
- Class 11 Chemistry Ch 13: Hydrocarbons
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