Study of Aqueous Solution of Strong Electrolyte—Reexamination of Molecular Refraction

Abstract

Molecular refraction of 1–1 electrolyte aqueous solution was reexamined in the light of a proposed model. So-called Lorentz-Lorenz function was plotted against molar fraction of electrolyte. Linear relationships and critical phenomenon dividing the whole range into two were found. By applying our theory we obtain total number of hydration, n_I⁽⁺⁾+n_I⁽⁻⁾+n_II⁽⁺⁾+n_II⁽⁻⁾, where the hydration numbers around each cation and anion are defined as n_I⁽⁺⁾, n_I⁽⁻⁾ referred to the primary region and n_II⁽⁺⁾, n_II⁽⁻⁾ referred to the secondary region respectively. We could also estimate the polarizability α_* of water molecule which are considered as ‘solvent in concentrated range’ and subjected to the sufficient effect of polarization from surrounding ions.