Physical organic chemistry heterogeneous systems

I don't quite understand the question. What are the first conditions and which one are variable?

Often the direction, selectivity of the processes, and hence the product yield, depend on the concentration.

Well if the liquids does not dissolve in one another that means that the reaction can only proceed on the face surface. It's definitely a smaller contact then in volume 

@_brauer_ The overall speed of the process will be determined by the diffusion rate. This means that the object of control will be the mass transfer rate of the process. The mass transfer rate depends on the mass transfer coefficient, the specific contact surface of the phases, the driving force of the process. It is the driving force that determines the difference in the concentrations of substances in each phase. Thus, the concentration of the dissolved substance will greatly affect. Moreover, this effect will be even stronger when the substance is completely dissolved in another phase.

@_brauer_ Moreover, the mutual solubility of the two solutions will affect the yield of the target product.

It is known that in the dissolved state, the mobility and chemical activity of molecules increases due to the solvation process.

@damiryagudin But solvation reduces the chemical activity of ions, molecules

@nanochimik47 But what about the transfer of solute and solvent particles in solutions by diffusion?

@_brauer_ In your question, you use the phrase "heterogeneous systems of two solutions". It is known that a solution is a homogeneous system consisting of two or more components. You're talking about heterogeneous systems. Where is the truth here? How correct is it to use such a phrase? What do you say about this?

@damiryagudin I don’t argue about that.

@damiryagudin Well, where a homogeneous system is more of a true solution, there are also colloidal solutions, dispersed systems)

@argentum These are all heterogeneous systems. I meant that two opposite concepts are used. Therefore, it would be more correct to say dispersed systems or two-phase heterogeneous systems in accordance with the Gibbs phase rule.

@damiryagudin Ok, I agree

I always thought that if there is two different phases system can be called heterogeneous