Ideal solutions entropy change

In review, we see that, for an ideal solution, the change of the Gibbs energy on mixing and the change of the entropy on mixing both at constant... 

As known, SEC separates molecules and particles according to their hydro-dynamic volume in solution. In an ideal case, the SEC separation is based solely on entropy changes and is not accompanied with any enthalpic processes. In real systems, however, enthalpic interactions among components of the chromatographic system often play a nonnegligible role and affect the corresponding retention volumes (Vr) of samples. This is clearly evident from the elution behavior of small molecules, which depends rather strongly on their chemical nature and on the properties of eluent used. This is the case even for... 

One of the approaches to calculating the solubility of compounds was developed by Hildebrand. In his approach, a regular solution involves no entropy change when a small amount of one of its components is transferred to it from an ideal solution of the same composition when the total volume remains the same. In other words, a regular solution can have a non-ideal enthalpy of formation but must have an ideal entropy of formation. In this theory, a quantity called the Hildebrand parameter is defined as ... 

Solutions of nonpolar solutes in nonpolar solvents represent the simplest type. The forces involved in solute-solvent and solvent-solvent interactions are all London dispersion forces and relatively weak. The presence of these forces resulting in a condensed phase is the only difference from the mixing of ideal gases. As in the latter case, the only driving force is the entropy (randomness) of mixing. In an ideal solution (AW, = 0) at constant temperature the free energy change will be composed solely of the entropy term ... 

What is the entropy change when 20 g of benzene and 20 g of toluene are mixed to form an ideal solution ... 

Calculate the entropy change, in calories/degree, that accompanies the separation of four components from one another in an ideal solution containing one mole of each. When separated, each component occupies one-quarter of the original volume. Deduce from your results whether or not the separation is thermodynamically spontaneous. 

An ideal solution is one in which the interactions between solute and solvent molecules are the same as those for the pure solvent and pure solute. It follows Raoult s law and has no heat of mixing, no entropy of mixing, and no change in volume on mixing. Very few solutions fit this model, so other, less ideal models have been proposed. 

Ideal solutions are defined as mixtures that have no volume or enthalpy changes upon mixing, but have an ideal entropy of mixing given by... 

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