Edexcel IGCSE Chemistry 复习笔记 4.3.2 Halogens & Alkanes

 

• In a substitution reaction, one atom is swapped with another atom
• Alkanes undergo a substitution reaction with halogens in the presence of ultraviolet radiation

 

 

In the presence of ultraviolet (UV) radiation, methane reacts with bromine in a substitution reaction

 

•  The equation for the reaction is

 

CH₄ + Br₂ → CH₃Br + HBr

 

methane + bromine → bromomethane + hydrogen bromide

 

• Chlorine will also react with alkanes to form chloromethane

 

CH₄ + Cl₂ → CH₃Cl + HCl

 

methane + chlorine → chloromethane + hydrogen chloride

 

• The products belong to a family called halogenoalkanes or haloalkanes
• Halogenoalkanes have many uses a solvents, refrigerants, propellants and pharmaceuticals

 

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