Faraday's law, also known as the law of electrolysis, is the basic law followed by the electric lock process. Faraday (Michael Faraday 1791-1867) was a British self-taught scientist . The electrolytic law he discovered still guides the electrodeposition technology. It is the most basic law in electrochemistry. Workers engaged in electric locks should all Familiar with this law . It is further divided into two sub-laws, Faraday's first law and Faraday's second law.
(1) Faraday's first law Faraday's research shows that in the process of electrolysis, the amount of the reduced substance precipitated on the cathode is proportional to the current intensity and energization time. When we discuss the electrodeposition of metals, the formula can be expressed as:
M=KQ=Klt
In the formula, M - the mass of precipitated metal;
K - constant of proportionality;
Q — the electricity passed;
I - current intensity;
t — power-on time.
Faraday's first law describes the qualitative relationship of electrical energy into chemical energy, and further research shows that this conversion has a strict quantitative relationship, which is what Faraday's second law wants to express.
(2) Faraday's second law In the process of electrolysis, if the electricity passing through is the same, the Dong of different substances that are precipitated or dissolved are the same. It can also be expressed as: The electricity required for electrolysis of 1 mol of substance is 1 " Faraday" (F)' equal to 96500 C or 26. 8A• h.
1F=26.8A h=96500C
Combined with the first law, it can also be said that when the same amount of electricity passes through different electrolyte solutions , the substances precipitated (or dissolved) on the electrodes are directly proportional to the Dong of their substances. Since molar numbers are now suggested in standard parlance, it is also possible to describe these theorems . The so-called mole is a unit that expresses the amount of a substance, and each mole of a substance contains Avogadro's number of particles. Mole is called Mo for short, and the symbol is mol. Since the number of atoms per mole of any substance is a constant, that is, 6.023 X 10 23 , this number is called Avogadro's constant. Avogadro's constant is a large value, but the mole is extremely convenient to use as a unit of quantity of matter. Because the mass of lmol 12 C is 12g, that is, the mass of 6.023 X 10 23 carbon atoms. From this, we can deduce the mass of lmol of any atom.
The relative atomic mass (atomic weight) of an element is based on 1/12 of the mass of 12 c as a standard. The value obtained by comparing the mass of any element atom with carbon is the atomic weight of the element, such as the atomic weight of oxygen is 16, the atomic weight of hydrogen is 1', the atomic weight of iron is 55.85, and so on. The ratio of the mass of one carbon atom to the mass of one oxygen atom is 12:16. One mole of carbon atoms has the same number of atoms as one mole of oxygen atoms. lmol carbon atom is 12g, then lmol oxygen atom is 16g. Similarly, the mass of any atom in lmol is in grams, which is numerically equal to the atomic weight of this kind of atom.
