condutimetria

Condutimetria, also known as conductimetria, is the measurement of the electrical conductivity of an aqueous solution to infer its ionic content and salinity. It is commonly used to estimate total dissolved solids and to monitor processes in chemistry, environmental science, and industry.

Principles and fundamentals: Conductivity reflects the ability of ions in solution to carry electric current. The measured conductance G is related to the solution’s conductivity κ by G = κ × K, where K is the cell constant determined by the geometry of the conductometric cell. Temperature strongly influences conductivity, so many instruments apply automatic temperature compensation to report conductivity at a reference temperature.

Instrumentation and methods: A conductometer or conductivity meter uses a conductivity cell with two or four electrodes. Calibration is typically performed with standard solutions (often potassium chloride). Two-electrode configurations are common for routine measurements, while four-electrode arrangements reduce electrode polarization errors for more precise work. Measurements can be reported as conductivity (S/m or µS/cm) or converted to approximate total dissolved solids (TDS) values.

Applications: Condutimetria is widely used in water analysis (drinking water, wastewater, groundwater, seawater), food and beverage production, pharmaceutical manufacturing, and industrial process control. It helps monitor salinity, ionic strength, contamination, and reaction progress.

Limitations and considerations: The method provides a bulk ionic indicator rather than speciation; it does not identify individual ions. Highly conductive or very dilute samples, complex matrices, or samples with organic interferences may require careful calibration and temperature control. Temperature, electrode condition, and cell geometry must be accounted for to ensure accurate results.