Apparent molar volume ionic solutes

A good approximation for the density of multicomponent electrolyte solutions can be obtained by adding the individual ionic contributions to the apparent molar volume ... 

The effective ionic volume of an ion in solution, the partial molar volume, can be determined via a quantity that is directly obtainable. This is the apparent molar volume of a salt, defined by... 

In terms of total surfactant concentration, appreciable binding of dodecyl-and cetylpyridinium cation starts at the same total concentration, at about 1 X 10 5 mol dm 3, irrespective of the ionic strength of solutions. Above this concentration the heat effects that accompany the complexation of surfactant with the polyelectrolyte increase sharply, and their value can be partly attributed to the micellization of detergent. The viscosity and apparent molar volume measurements reveal that above cs 1 X 10 5 mol dm-3 extensive coiling of the chain around surfactant micelles takes place. In addition to this, the unusual behavior of molar conductivity in polyelectrolyte-surfactant solutions shows that an appreciable amount of small counterions may... 

It should be pointed out that the ionic association in NaOH aqueous solutions is important at temperatures above 523 K and the extrapolation of the apparent molar volume in this case was performed using Equation (2.29) for associated electrolytes. 

Ionic Molar Volumes in Aqueous Solutions The densities, p, of electrolyte solutions, as dependent on their concentrations at constant temperatures and pressures, are measurable with high accuracy. In a solution made up from moles of water and moles of electrolyte, the total volume of the solution is V=Mlp, where The apparent molar volume of an electrolyte, Vg, is the... 

The influence of different ionic media (KCl and NajCit) on the volumetric properties of citric acid solutions is illustrated in Figs. 2.18 and 2.19. The apparent molar volume of citric acid F2( (H3Cit) is considerably larger than that of potassium chloride V (K.Ci) and it is always observed that... 

Since behaviour of the F2 3 =fC/w. ) and F2 =g(7) functions is similar, it is possible to replace by the ionic strength of solution, I=6m +m. However, the use of is preferable, considering that for dtiates usually we iWe I m which leads to reduction of concentration scales in figures. As can be observed, in all cases of strong electrolytes, with increasing the expected order of the mean apparent molar volumes is achieved only for dilute solutions. In concentrated solutions, values are even larger than... 

A single homogeneous phase such as an aqueous salt (say NaCl) solution has a large number of properties, such as temperature, density, NaCl molality, refractive index, heat capacity, absorption spectra, vapor pressure, conductivity, partial molar entropy of water, partial molar enthalpy of NaCl, ionization constant, osmotic coefficient, ionic strength, and so on. We know however that these properties are not all independent of one another. Most chemists know instinctively that a solution of NaCl in water will have all its properties fixed if temperature, pressure, and salt concentration are fixed. In other words, there are apparently three independent variables for this two-component system, or three variables which must be fixed before all variables are fixed. Furthermore, there seems to be no fundamental reason for singling out temperature, pressure, and salt concentration from the dozens of properties available, it s just more convenient any three would do. In saying this we have made the usual assumption that properties means intensive variables, or that the size of the system is irrelevant. If extensive variables are included, one extra variable is needed to fix all variables. This could be the system volume, or any other extensive parameter. 

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