electrolyte solution is a special liquid that partially or completely in the form of charged particles (ions).The process of splitting molecules on the negative (anions) and positively charged (cations) particles called electrolytic dissociation.Dissociation in solution is only possible due to the ability of the ions to interact with the molecules of the polar liquid, which acts as a solvent.
What are electrolytes
electrolyte solution are divided into aqueous and nonaqueous.Water studied quite well and were very widespread.They are in almost every living organism and is actively involved in many important biological processes.Nonaqueous electrolytes apply for electrochemical processes and various chemical reactions.Their use has resulted in the invention of new sources of chemical energy.They play an important role in photoelectrochemical cells, organic synthesis, electrolytic capacitors.
electrolyte solution according to the degree of dissociation can be classified into strong, medium and weak.The degree of dissociation (α) - is the ratio of the broken molecules on the charged particles to the total number of molecules.In strong electrolytes value α is close to 1, y averages α≈0,3, and the weak α & lt; 0,1.
By strong electrolytes typically include salt, a number of certain acids - HCl, HBr, HI, HNO3, H2SO4, HClO4, hydroxides of barium, strontium, calcium and alkali metals.Other acids and bases - electrolyte medium or weak strength.
properties of electrolyte solutions
Education solutions often accompanied by thermal effects and changes in volume.The process of dissolution in the liquid electrolyte is held in three stages:
- destruction of chemical bonds and intermolecular dissolved electrolyte requires the expenditure of a certain amount of energy and therefore heat is absorbed (ΔNrazr & gt; 0).
- At this point the solvent begins to interact with the ions of the electrolyte, resulting in formation of solvates (in aqueous solution - hydrates).This process is known and is exothermic solvation, i.e.takes heat (Δ Ngidr & lt; 0).
- last stage - diffusion.This uniform distribution of hydrates (solvates) in the bulk solution.This process requires the expenditure of energy and therefore the solution is cooled (ΔNdif & gt; 0).
Thus, the total thermal effect of the dissolution of the electrolyte can be written in this form:
ΔNrastv ΔNrazr + = + ΔNgidr ΔNdif
on what will constitute the final energy effects depends on the sign of the total thermal effect of the dissolution of the electrolyte.Typically, this process is endothermic.
properties of the solution depends primarily on the nature of its constituent components.Furthermore, the properties of the electrolyte composition of the solution affects the pressure and temperature.
Depending on the content of all of the solute electrolyte solutions can be divided into very dilute (which contain only a "trace" of the electrolyte), dilute (containing a small amount of solute) and concentrated (with a high content of electrolyte).
Chemical reactions in electrolyte solutions, which are caused by the passage of electric current leads to the release of specific substances on the electrodes.This phenomenon is called electrowinning, and is often used in modern industry.In particular, due to electrolysis prepared aluminum, hydrogen, chlorine, sodium hydroxide, hydrogen peroxide, and many other important matter.
