Chapter VIII - The effects of salts on the molecular organization of H2O: 1-propanol (1P)-probing methodology

Abstract

This chapter examines the effects of various salts (and the constituent ions) on the molecular organization of H2O using the 1P-probing methodology. Based on this, it demonstrates the effects of cations and anions on the molecular organization of H2O. This approach has provided important advances through analysis of various factors including surface tension increments, lyotropic number, viscosity B-coefficients, zetapotentials, salt activities, etc. Also, the effects of ions on the structure and the function of biopolymers in aqueous solutions have been studied extensively. As a result, ions have been ranked as the Hofmeister series according to the propensity and the strength of the effect of each ion. The generality of this ion ranking for a wide range of processes has sparked a massive interest in the possible underlying mechanism. However, the molecular level understanding of the Hofmeister effect is still fragmentary. This chapter makes an attempt at sorting out the ranking in terms of the hyrophobicity/hydrophilicity scale within the methodology . In addition, it explains that the method could identify some ions as simple hydration centers without altering the nature of bulk H2O. The hydration number of these ions could be evaluated by this method. Finally, it describes that for such ions the Hofmeister ranking is consistent with Hofmeister’s original idea, “water withdrawing power.”