In the reaction,
$R O R'+ HX \longrightarrow R O H+R^{\prime} X$
the correct order of reactivity of halogen acids is :
$HI > HBr > HCl$
The smaller alkyl group always forms alkyl halide while bigger alkyl group
(or aryl group) forms alcohol (or phenol).
$CH _{3} OCH \left( CH _{3}\right)_{2}+ HI \longrightarrow CH _{3} I +\left( CH _{3}\right)_{2} CHOH$$CH _{3} OC _{6} H _{5}+ HI \longrightarrow CH _{3} I +\underset{\text { Phenol }}{ C _{6} H _{5} OH }$
Alcohol is formed when a saturated carbon atom bonds to a hydroxyl (-OH) group. It is an organic compound that contains a hydroxyl functional group attached to a carbon atom.
Phenol is formed when the -OH group replaces the hydrogen atom in benzene. It is an organic compound in which a hydroxyl group directly attaches to an aromatic hydrocarbon.
Ether is formed when oxygen atom bonds to two alkyl or aryl groups. It is an organic compound that has an oxygen atom that is connected to two aryl and alkyl groups.
