Specific electrical conductivity characterizes the ability of substances to conduct electric current, this value is inversely proportional to electrical resistivity.
When it comes to the specific value, it means finding the measure of the parameter for the unit of the characterized object. Let's start with simple, common examples that will help you quickly understand the essence of what is happening.
Specific gravity is the simplest parameter showing the mass of one cubic meter of a substance under normal conditions. In this case, the measure of the parameter is the kilogram, and the unit of the object is the cubic meter.
The condition for carrying out measurements under normal conditions is introduced for definiteness, since with an increase in pressure, strictly speaking, a cubic meter of a substance will have a mass greater than at normal pressure. Looking ahead, we note that semiconductors, for example, can change their electrical resistance in a very noticeable way whenchange in temperature or light.
Now back to the question of what is electrical conductivity. As mentioned above, this value is the reciprocal of the resistivity, which in turn is interpreted as follows:
Resistivity is the resistance of a cube of matter with a side of 1 meter to electric current, provided that the current flows strictly perpendicular to one of the faces of the cube. Conductivity can be interpreted in a similar way, but it is worth adding that the requirements for measurements under normal conditions are also vital for this case.
At the moment, science believes that electrical conductivity is directly proportional to the square of the charge of the particles that form the current, their number in matter per volume, and inversely proportional to the mobility of charge carriers. In understanding this interpretation lies the explanation of why Ohm's law does not apply to gases. At a certain value of the electromagnetic field strength, the ionization process occurs, and the current grows like an avalanche. Which is used in welding or in elementary fluorescent lamps.
As for solutions, the situation is much more interesting if you approach them from these positions. The electrical conductivity of solutions depends primarily on the number of charge carriers, which are free ions charged negatively or positively. Since there are no such ions in pure distilled water,then the specific electrical conductivity of water is close to zero. This means that the current through clean water will not go. Methods for measuring mineralization or water pollution, in particular the ph factor, are based on this phenomenon.
Specific electrical conductivity is the very decisive moment that forces the use of precious metals in electronics. Due to the extremely high value of this parameter, noble metals become an essential element of the most accurate measuring technology. Few people know that the reflectivity of a metal also largely depends on its resistance, which is why mirrors were often made of silver.
