Conductivity mechanism in electrolytic solutions
Electrolytic cell
It is an electrochemical cell where electrical energy is converted into chemical energy as a result of passing an electric current an external source, leading to a chemical reaction.
Electrolysis
It is a chemical reaction that occurs as a result of passing an electric current through an electrolytic cell. In this process, oxidation reactions of negative ions occur at the anode, while reduction reactions of positive ions occur at the cathode, resulting in the liberation or deposition of substances.
The conductivity mechanism in ionic solutions is primarily based on the movement of charged ions within the solution, these ions can conduct electricity in solutions because they can to move. The more ions present in a solution, the higher the conductivity measurement will be.
In a solution such as water, conductivity comes from the passing of electricity between ions. For example, when sodium (Na+) and chlorine (Cl-) form sodium chloride in saltwater, more electricity is carried, and therefore the conductivity increases. As salinity increases, conductivity also increases.
To measure the conductivity of an ionic solution, we use a conductivity cell, which consists of two metallic plates indicated to as the electrodes. The area of the cell immersed in the solution is S in square meters (m²) and a distance L in meters (m) between the electrodes. As shown in Figure 2

Conductivity
The electrical conductivity σ is a measure of a material's ability to conduct or transmit electricity.
The conductivity has a direct relation with the molar concentration of the solution and the molar specific conductivity λ, it is expressed in Siemens per meter S/m.
• It is also known as the reciprocal of resistivity
σ: Electrical conductivity (S/m).
λ-: Specific molar conductivity of the anion ion S.m2/mol.
λ+: Specific molar conductivity of the anion ion S.m2/mol.
[X- ]: Molar concentration of the anion ion mol.
[X+ ]: Molar concentration of the cation ion mol.
ρ: The resistivity of the solution Ohm. meter (Ω.m).
Conductance
It is a physical quantity that expresses the conductance of an electric current. Its symbol is G, and it is expressed in Siemens (S).
It is also known as the reciprocal of resistance.
Resistance
Resistance is the capability of a conducting material to permit the passage of electric current, it depends on its geometric shape (material's composition, length, cross-sectional area), and it is expressed in Ohm (Ω).
R: The resistance of the material Ohm (Ω).
U: Tension difference between the terminals of the material Volt (V).
I: Intensity of electric current Ampere (A).
Resistivity
Based on resistivity, we can compare different materials based on their ability to conduct electrical currents, and it is expressed in Ohm. meter (Ω.m).
ρ: The resistivity of the solution Ohm. meter (Ω.m)
R: The resistance of the material Ohm (Ω).
K: Cell constant meter (m).






