Which ions has exceptionally higher ${\mathrm{\lambda }}^{\mathrm{\infty }}$ values ?

detailed solution

Correct option is A

The hydrogen ion, because of its small size has high charge density and is heavily hydrated. Thus, we expect the mobility of H+ ion to be low rather than high.The high mobility of H+ ions is hydroxlytic solvents such as H2O can be explained by Grouttus type meachanism in which a proton moves rapidly from H3O+ to a hydrogen-bonded water molecule and is transferred along a series of hydrogen bonded water molecules by a rearrangement of hydrogen bonds (just like a relay race).Amongest negatives ions, OH- has the highest ionic mobility.