John is correct, but partial molar volumes may actually tell you a little bit about the interaction between the different components of the mixture and the local structure of the solvent. In particular in water effects in the partial molar volume may be seen due to breaking of local water structure or even creating ice like structures ("iceberg model") around hydrophobic solutes. Having said that, the line between local structure and partial molar volume is long and very convoluted. There is a theory called Kirkwood-Buff theory in which the partial molar volumes (together with other thermodynamic parameters) can be related to integrals over the pair correlation functions between solvent and solute molecules. In the past (maybe even still, but I am not familiar with current research in this area, I briefly worked with such a group in the middle 1980's) people tried to use these theories also to understand thermodynamic properties of solutions of amino acids and small peptides. Success was very limited.

As an example: try to understand the behavior of the partial molar volumes for low ethanol concentrations in water-ethanol mixtures. The figure can be found in many textbooks.

In addition there is a formal, so-called Maxwell-relation between the partial molar volume and the pressure dependence of the chemical potential of a component that may be useful if you need one and can measure the other.

Often the total volume of a solution is not simply the sum of the volumes of the components. The partial molar volume of the components allows one to correct for this difference.

Useful reference: Physical Chemistry, 2nd Ed., Berry, Rice and Ross, p. 669

John is correct, but partial molar volumes may actually tell you a little bit about the interaction between the different components of the mixture and the local structure of the solvent. In particular in water effects in the partial molar volume may be seen due to breaking of local water structure or even creating ice like structures ("iceberg model") around hydrophobic solutes. Having said that, the line between local structure and partial molar volume is long and very convoluted. There is a theory called Kirkwood-Buff theory in which the partial molar volumes (together with other thermodynamic parameters) can be related to integrals over the pair correlation functions between solvent and solute molecules. In the past (maybe even still, but I am not familiar with current research in this area, I briefly worked with such a group in the middle 1980's) people tried to use these theories also to understand thermodynamic properties of solutions of amino acids and small peptides. Success was very limited.

As an example: try to understand the behavior of the partial molar volumes for low ethanol concentrations in water-ethanol mixtures. The figure can be found in many textbooks.

In addition there is a formal, so-called Maxwell-relation between the partial molar volume and the pressure dependence of the chemical potential of a component that may be useful if you need one and can measure the other.

That was truly a beautiful exposition by Gert, and reminds me of another reference you probably would like to peruse that discusses clathrates. The text is "Proteins, 2nd Edition" by Creighton. All of chapter 4.

Best regards.

Two important facts about partial molar volumes:

1. The partial molar volume is a function of mixture composition. For example in a mixture of 10% ethanol (by mole) and 90% water, the partial molar volume of water is about 18.1 cm3 per mole, whereas in a mixture of 90% ethanol and 10% water the partial molar volume of water is around 14.5 cm3 per mole. The values above reflect the effect of the molecular environment on the volume occupied by solute/solvent molecules. It is necessary to note that the relation between partial molar volumes and mixture composition is far from linearity.

2. When a solute is added to a solvent, the result is not always an increase in total volume (of the solution). One famous example is the decrease in solution volume by 1.4 cm3 when 1 mole of MgSO4 is added to a large volume of water.

Apart from the partial molar volume, the concept of partial molar quantity makes it possible to define the chemical potential as the partial molar Gibbs energy. This has a central importance in defining equilibrium and in understanding/interpreting some thermodynamic properties of solutions.

See Ch. 5 in Atkins/8e

Partial molar volumes of binary mixtures are efficiently discussed via Kirkwood-Buff theory (jyst as Gert reported), when activity coeffients are also available, to extract information of preferential solvation. An excellent review is

Kenneth E. Newman "Kirkwood-Buff Solution Theory: Derivation and Applications" Chem. Soc. Rev. 1994, pp 31-40

In ternary and quaternary systems there are also some recent attempts: see rigorous thermodynamic works by E. Ruckenstein and I. Shulgin.

See "Chemical and Engineering Thermodynamics, second edition, autor: Stanley I. Sandler, 1989, pgs:257-258; 279-284

Thank you for your answers but

may i know is this study having industrial or any other applications.

Given the replies that you got so far I would say the answer is clearly yes ("industrial" I don't know, "any other" definitely). If you are looking for something in particular, I would suggest Google Scholar (or, if you have access to it, Web of Science) to ask for "Kirkwood Buff theory". It will give you a list of several thousands of links to papers. If there is one that you find interesting but have no access to, I, or one of the other respondents could conceivably help you.

While I agree with Gert, I wish to remark that partial molar volumes, excess volumes, and similar properties are rather useless as means of studying fluid structure if studied at one temperature and ambient pressure only. There are mixtures which exhibit a positive excess volume at one pressure and a negative at another. Forming hypotheses about local structure or interaction between molecules on the basis of excess volume curves alone is dangerous.

Knowing excess volumes or partial molar volumes *over a wide range of pressures and temperatures may be very useful*; in particular having VE as a function of pressure allows the computation of the excess Gibbs energy.

Because this helps you to choose the solute and solvent especially in making alcoholin water in order to determine the total volume os the solution exactly

Knowledge of physical properties of liquids and excess thermodynamic functions for mixing process is essential for good design of industrial chemical process and for testing theories on liquid mixtures. Among these excess functions, the volume change on mixing is one of the most interesting because it is a good thermodynamic tool to explore the behaviour of liquid systems and, also, a sensitive indicator to accuracy of liquid mixture theories.

Knowledge of partial molar properties at infinite dilution, especially, provides useful information about solute-solvent interaction since, at the infinite dilution, solute-solute interactions disappear. This information is of particular interest because it is independent of the composition of the mixture

Excess molar volume (VE) depends Mainly on packing effect and the molecular interaction between like and unlike species of the solution so if the VE is negative this means that there is a strong interaction between unlike species and that there is a strong packing effect. The positive VE means the reverse.

Partial molar volumes help to assess the influence of pressure on phase equilibria or reaction equilibria. The prediction of partial molar volumes or excess volumes is a sharp test for theories of the fluid state.

On the other hand, the interpretation of partial molar volumes or excess volumes is usually difficult, if not impossible. Many mixtures exhibit positive and negative excess volumes, depending on composition, temperature, and pressure. Speculations why some mixture exhibits positive or negative excess volumina are futile, particularly if they are based on measurements at ambient pressure and temperature only.