called electrolysis process, characterized redox properties in respect of the constituent elements of salts and other compounds present in the melt or solution, by passing an electric current through them.
By means of electrolysis can be obtained non-metals and metals with a high degree of chemical purity.This reaction is characterized by simplicity and affordability, it is even possible to simulate at home.This will require a source of direct current, a pair of electrodes and an electrolyte prepared beforehand.The most basic property of electrolytes is their ability to conduct electricity.
Distinguish electrolysis solutions and molten salts, with an overall similarity, they have some significant differences.Through electrolysis solutions should be involved in the process solvent and ions.Electrolysis of melts is characterized by the presence of only ions of the substance itself.
to obtain the desired product (be it metal, gas, or any non-metal) should be concerned about the selection of a suitable electrode and the electrolyte of the respective preparation.
materials for electrodes can serve as any conductor of electric current.In most cases, metals and alloys, including non-metals good performance as an electrode can show graphite rods (carbon).It is very rare, but known technological solutions, which are used for the electrode material liquid.
Everything is ready to carry out the electrolysis of salt solutions.The positive electrode called the anode.For a negative electrode made designation - cathode.Through electrolysis solution, the anode is oxidized (dissolved), and the cathode is restored.It is important that "dissolution" of the anode did not affect the chemical process that occurs in solution (melt).Otherwise - the main condition for the anode is its inertia.Ideally, it can be made of platinum, but the graphite (carbon) anode also very effective.
cathode suitable for almost any metal plate (it will not dissolve).Copper, brass, carbon (graphite), zinc, iron, aluminum cathodes are widely used in modern industry.
Through electrolysis solutions in the home, from virtually scrap materials available substances such as oxygen, chlorine, hydrogen, copper, or alkali weak acid, sulfur.You should not abuse the experiments with chlorine - it is poisonous!
For oxygen and hydrogen must be subjected to electrolysis solution of baking soda (an alternative - soda ash).Near electrode "+" (anode) is isolated in the form of bubbles oxygen at the cathode ("-") - hydrogen.When asked why there was a restoration of hydrogen instead of sodium as you might expect, you can find the answer in the electrochemical series of metal Na is left of H2, respectively, in the competition of the two cations hydrogen defeated sodium.The example of this reaction, we have witnessed the electrolysis solution, in fact, turned into the electrolysis of the solvent (water).
using as an electrolyte solution of copper sulphate, we get on the cathode dark red plaque, which is a pure metal, recover copper.
According to the results of two experiments on electrolysis can make some generalizations.Positive anode becomes a place for the recovery of anions, in both the above cases, they considered proved oxygen.At the cathode, recovering the cations in our experiments they were hydrogen - in the first case, copper - in the second.Generally, the cations are metals or hydrogen, but in some cases they may turn out to be non-metals and gases.The oxidation state of the element plays an important role in the recovery process.
