KCET2021ChemistryHydrocarbons
Peroxide effect is observed with the addition of HBr but not with the addition of HI to unsymmetrical alkene because
Options
- AH - I bond is stronger than H - Br and is not cleaved by the free radical
- BH - I bond is weaker than H - Br bond so that iodine free radicals combine to form iodine molecules
- CBond strength of HI and HBr are same but free radicals are formed in HBr
- DAll of the above
Correct answer
B. H - I bond is weaker than H - Br bond so that iodine free radicals combine to form iodine molecules
Step-by-step solution
Peroxide effect is observed with addition of HBr but not with the addition of H - I to unsymmetrical alkene because H - I bond is weaker than H-Br bond. So, unstable iodine free radicals combine to form stable iodine molecules as i.e.,