A-Level CAIE Chemistry AS 15.1.1—Preparation of halogenoalkanes Question Bank

• Recall preparation of halogenoalkanes

- (a) the free-radical substitution of alkanes by Cl 2 or Br2 with ultraviolet light, as exemplified by the reactions of ethane

- (b) electrophilic addition of an alkene with a halogen, X 2, or hydrogen halide, HX(g), at room temp.

- (c) substitution of an alcohol, e.g. by reaction with HX(g); or with KCl and conc. H2SO4 or conc. H3PO4; or with PCl 3 and heat; or with PCl5; or with SOCl 2