NEET2002ChemistryHaloalkanes and HaloarenesActual
Reactivity order of halides for dehydrohalogenation is:
Options
- AR-F > R-Cl > R-Br > R-I
- BR-I > R-Br > R-Cl > R-F
- CR-I > R-Cl > R-Br > R-F
- DR-F > R-I > R- Br > R-Cl
Correct answer
B. R-I > R-Br > R-Cl > R-F
Step-by-step solution
The alkyl halides are very reactive due to highly polarized R - X bonds with a large difference in electronegativities of carbon and halogen atoms. Thus, reactivity of R - X depends on bond length.More be the bond length, easier for the R - X to go for dehydrohalogenation. Related Theory Halogens increase in reactivity from the bottom to the top of their Group.