Explain the electrical conductivity of water?
Answers
The electrical conductivity of water is its ability to conduct an electric current. Salts or other chemicals that dissolve in water can decompose into positively charged and negatively charged ions. These free ions in the water conduct electricity so that the electrical conductivity of the water depends on the concentration of ions. Salinity and total dissolved solids (TDS) are used to calculate the EC of water, which indicates its purity. The purer the water, the lower the conductivity. To give a concrete example, distilled water is almost an insulator, but salt water is a very efficient electrical conductor.
The main positively charged ions that affect the conductivity of water are sodium, calcium, potassium and magnesium. The main negatively charged ions are chlorides, sulfates, carbonates and bicarbonates. Nitrates and phosphates contribute little to conductivity, but they are very important biologically. The natural impacts on EC in the water are rain, geology and evaporation. Human impacts include road salt, septic/landfill leachate, impervious surface runoff and agricultural runoff.