Focus on the classification, naming conventions, and isomerism types in haloalkanes. Includes practice problems and explanations for chemistry exam preparation.
A geminal dihalide has two halogens on the same carbon. CH₃CHCl₂ (1,1-dichloroethane) is a geminal dihalide.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
This is a Finkelstein reaction, where an alkyl bromide reacts with NaI in acetone to form the corresponding iodide, CH₃CH₂I , and NaBr precipitates.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
SN₂ reactivity increases with better leaving group ability: CH₃CH₂I > CH₃CH₂Br > CH₃CH₂Cl > CH₃CH₂F .
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
Free radical halogenation of propane ( CH₃CH₂CH₃ ) with Cl₂ forms CH₃CHClCH₃ (2-chloropropane) as one product.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
PCl₅ reacts with 1-butanol ( CH₃CH₂CH₂CH₂OH ) to form 1-chlorobutane ( CH₃CH₂CH₂CH₂Cl ) with POCl₃ and HCl as byproducts.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
Alkenes react with hydrogen halides (e.g., HBr ) via electrophilic addition to form alkyl halides. CH₃CH₂CH₂Br can be made from CH₃CH=CH₂ with HBr (peroxide conditions).
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
This is a Wurtz reaction, where two alkyl halides couple to form an alkane. CH₃CH₂Cl forms CH₃CH₂CH₂CH₃ (butane).
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
SN₁ reactivity depends on carbocation stability: tertiary > secondary > primary.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
For 1-butene ( CH₂=CHCH₂CH₃ ), HBr adds via Markovnikov's rule, forming CH₃CHBrCH₂CH₃ (2-bromobutane).
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
HCl with ZnCl₂ (a Lewis acid) converts ethanol to ethyl chloride ( CH₃CH₂Cl ) by facilitating substitution of the OH group.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
Pentane ( CH₃CH₂CH₂CH₂CH₃ ) has three unique carbon positions for Cl substitution (C₁/C₅, C₂/C₄, C₃), yielding 3 isomers.
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
For 2-pentene ( CH₃CH=CHCH₂CH₂CH₃ ), HBr adds via Markovnikov's rule, forming CH₃CHBrCH₂CH₂CH₃ (2-bromopentane).
Ref: NCERT Class 12 Chemistry > Chapter 6: Haloalkanes and Haloarenes > Topic: Classification and Nomenclature and Isomerism of Haloalkanes
