Faraday's laws are, in effect, basic principles according to which there takes place electrolysis. They establish connection between the quantity of electricity and substance emitted on electrodes.
The first law of Faraday
Electrolysis is the physical and chemical process which is carried out in solutions of various substances by means of electrodes (cathode and the anode). There is a set of substances which chemically decay on components when passing through their solution or fusion of electric current. They are called electrolytes. Many acids, salts and the bases concern them. Distinguish strong and weak electrolytes, but this division is conditional. In certain cases weak electrolytes show properties strong and vice versa.
At transmission of current through solution or fusion of electrolyte settle various metals (in case of acids hydrogen is just emitted) on electrodes. Using this property, it is possible to count the mass of the emitted substance. For similar experiments use solution of copper vitriol. On the coal cathode at transmission of current it is possible to see a red copper deposit easily. The difference between values of its masses before and after an experiment will also be the mass of the accumulated copper. It depends on quantity of electricity which passed through solution.
The first law of Faraday can be formulated so: the mass of substance m emitted on the cathode is directly proportional to quantity of electricity (to electric charge q), passed through solution or fusion of electrolyte. This law is expressed by a formula: m=KI=Kqt, where K - proportionality coefficient. It is called an electrochemical equivalent of substance. For each substance it accepts various values. It is in number equal to the mass of the substance emitted on an electrode in 1 second at the current of 1 ampere.
The second law of Faraday
In special tables it is possible to look at values of an electrochemical equivalent for various substances. You will notice that these values significantly differ. The explanation for such distinction was offered by Faraday. It turned out that the electrochemical equivalent of substance is directly proportional to its chemical equivalent. This statement carries the name of the second law of Faraday. Its validity was confirmed experimentally. The formula expressing the second law of Faraday looks so: K=M/F*n, where M - molar weight, n - valency. The relation of molar weight to valency is called a chemical equivalent. Size 1/F has the same value for all substances. F is called Faraday's constant. It is equal to 96.484 C/mol. This size shows quantity of electricity which needs to be passed through solution or fusion of electrolyte that settled one mole of a substance on the cathode. 1/F shows how many the mole of a substance will settle on the cathode when passing a charge to 1 C.