define hardness of water and explain the determination of hardness of EDTA method
Answers
Answer:
Hardness of water is determined by titrating with a standard solution of ethylene diamine tetra acetic acid (EDTA) which is a complexing agent. Since EDTA is insoluble in water, the disodium salt of EDTA is taken for this experiment. EDTA can form four or six coordination bonds with a metal ion.
Answer:
The hardness of water is due to the presence of soluble bicarbonates, chlorides and sulfates of calcium and magnesium. Water which does not give lather with soap is hard water.
Explanation:
The estimation of hardness is based on complexometric titration. Hardness of water is determined by titrating with a standard solution of ethylene diamine tetra acetic acid (EDTA) which is a complexing agent. Since EDTA is insoluble in water, the disodium salt of EDTA is taken for this experiment. EDTA can form four or six coordination bonds with a metal ion.
EDTA is an acid used to dissolve “limescale,” which is a kind of mineral made primarily of calcium carbonate that often builds up over time in water pipes, tanks, etc. The EDTA method involves titrating EDTA into a sample of water. The amount of EDTA required to fully react with all of the dissolved calcium in the water can be used to determine the “hardness” of the water.