Question

why does halogenation take place at higher temperature or in the presence of sunlight

Answer 1

Dear Student,

The halogenation reaction involves the use of halogen gas which can be Cl₂ or Br₂. The Cl-Cl or Br-Br bonds are very strong as both the atoms are same on the sides. The bond is called as homolytic bond. The homolytic bonds are very strong and has high bond dissociation energy. These bonds do not break at room temperature and need lot of energy to break. The energy is provided by high temperature or UV-light to produce radicals which initiate the halogenation reactions of organic compounds.

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