Halogenoalkanes - exam practice

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electrophilic addition

nucleophilic addition

free radical substitution

nucleophilic substitution

CCl₃F

CF₄

CHClF₂

CH₂F₂

•CH₂Cl

•CH₂Br

•CHBrCl

•CH₂BrCl

homolytic fission

heterolytic fission

an initiation reaction

a propagation reaction

NH₃ attacks the halogen atom

NH₂^- attacks the carbon atom next to the halogen

NH₃ forms a bond with its lone pair to the carbon atom next to the halogen

the halogen atom is lost as a radical

fluoroethane has the higher boiling point because it forms hydrogen bonds

fluoroethane has the higher boiling point because the C-F bond is stronger than C–I

iodoethane has the higher boiling point because it forms the stronger instantaneous dipole–induced dipole bonds

iodoethane has the higher boiling point because the C-I bond is less polar than C-F

the C-I bond enthalpy is greater than the C-Cl bond enthalpy

the C-I bond is less polar than the C-Cl bond

the C-I bond has a C atom with a greater δ⁺ charge than in the C-Cl bond

the C-I bond requires less energy to break than the C-Cl bond

CH₃CH₂CH₃ + Br• ➔ CH₃CHCH₃• + HBr

O₃ + ClO• ➔ Cl• + 2O₂

RO• + H₂C=CH₂ ➔ ROCH₂CH₂•

CH₃CFCl• + Cl• ➔ CH₃CFCl₂

fluorine is highly electronegative

the F^- ion is very stable

they are polar molecules

the C-F bond is very strong

•CH₂Cl + Cl• ➔ CH₂Cl₂

•CH₃ + •CH₃ ➔ C₂H₆

Cl₂ ➔ Cl• + Cl•

CH₃Cl + Cl• ➔ •CH₂Cl + HCl

CH₃CH₂CHBr• + Br₂ ➔ CH₃CH₂CHBr₂ + Br•

O₃ + Cl• ➔ O₂ + ClO•

RCH₂CH₂• + H₂C=CH₂ ➔ RCH₂CH₂CH₂CH₂•

CH₃CFCl₂ ➔ CH₃CFCl• + Cl•

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(C₂H₅)₂NH₂⁺Cl^-

C₂H₅NH₄⁺Cl^-

NH₂CH₂COCl

C₂H₅NHCOC₂H₅