Calcium and Magnesium are often present in soil as carbonates (e.g.: dolomite), sulfates (in arid regions) and silicates. They are necessary nutrients for plants since they have an important role in plant metabolism and growth. They can be removed from soil by leaching (for instance in acidic soil of humid regions) or by crop production; a deficiency of calcium and magnesium in soil will manifest itself in stunted growth and in yellow and deformed leaf tips. On the other hand, soil with an excess of calcium and magnesium will lock up other necessary micronutrients, making them unavailable to plant roots (e.g.: available phosphorus forms an insoluble salt with calcium at pH values above 7.5, thus decreasing the efficiency of applied phosphorus fertilizers).
The HI 38081 test kit determines calcium and magnesium in irrigation water via a titrimetric method. The indicator chelates with the calcium and magnesium ions to form a red colored complex. As EDTA is added, calcium and magnesium complex with it, and the reaction endpoint is indicated by a change in color of the indicator from red to blue.
Order Information:
HI 38081 test kit comes with 30 mL Ca & Mg reagent, 120 mL EDTA solution (2), 10 mL calmagite indicator, demineralizer bottle for 12 L, 50 mL calibrated vessel, 1 mL plastic pipette, 3 mL plastic pipette and 1 mL syringe with tip.
Manual: Download
Method | Titration | |
Range | >0.0 meq/l | |
Smallest Increment | 0.2 meq/l | |
Chemical Method | EDTA | |
Number of Tests | approx. 100 | |
Weight | 671 g |