What is the partial molar volume of NaCl?
Standard partial molar volumes range from 8.0 cm3-mol−1 at 175°C to −600 cm3-mol−1 at 350°C.
Why does partial molar volume vary with concentration?
The partial molar volumes are found to increase with increasing temperature over the entire concentration range investigated in a given mixed solvent medium whereas these values are found to decrease as the relative permittivity of the medium decreases.
What is the difference between molar volume and partial molar volume?
Molar volume is the volume of one mole of a substance. The main difference between molar volume and partial molar volume is that molar volume of a substance is the volume of one mole of that substance whereas partial molar volume is the change in volume of a mixture when a component is added to that mixture.
What is meant by partial molar volume?
In general, the partial molar volume of a substance X in a mixture is the change in volume per mole of X added to the mixture. The partial molar volumes of the components of a mixture vary with the composition of the mixture, because the environment of the molecules in the mixture changes with the composition.
What is partial molar volume in chemistry?
The partial molar volume is broadly understood as the contribution that a component of a mixture makes to the overall volume of the solution. When one mole of water is added to a large volume of water at 25 °C, the volume increases by 18 cm3. The molar volume of pure water would thus be reported as 18 cm3 mol−1.
What is the purpose of partial molar volume?
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.
Why is partial molar volume important?
Partial molar volume is an important thermodynamic property that gives insights into molecular size and intermolecular interactions in solution. Thermodynamically, V° can also be determined as the pressure derivative of the free energy of solvation in the limit of infinite dilution.
What is meant by partial molar quantities?
Why partial molar volume is negative?
As shown in Fig. 5.3 a) partial molar volumes can also be negative, e.g. for salts which decrease the volume of a solution when added. Of course the decreasing volume (shrinking) of the mixture when adding the solute (B) is interrelated with negative values of the partial molar volumes.