# How does the cation radius affect the rate of increase of the electrical conductivity of a salt in aqueous solution?

Potassium chloride has a greater ionic radius than sodium chloride. How does this affect the fall in rate of increase in conductivity as concentration concentrations? I know the following factors affect the plateauing of the curve:

lesser dissociation, the equilibrium is disturbed as a result of lack of water molecules to fully solvate the ions, ionic pair association and the increased visocity of the solution

In my experiment I found that the decraase of the rate of increase was greater for KCl, which I found weird.

• Ionic radius is not the same as the effective hydrated ionic radius. Their orders for Li Na K are mutually reversed. – Poutnik Nov 28 '20 at 0:09
• It rather affect ion mobility and therefore molar conductivity. Smaller ions have stronger field and therefore thicker effective AVG layer of attached water molecules bound to it and following its electromigration. – Poutnik Nov 28 '20 at 0:21
• Molar conductivity is better parameter than conductivity. $\Lambda = \kappa/c$ BTW I was addressing differences between ions, not concentration effect . – Poutnik Nov 28 '20 at 0:26
• – Poutnik Nov 28 '20 at 0:30
• @Strawhat It would be nice if you could stop vandalizing your own posts. – andselisk Nov 28 '20 at 8:43