The HI-3812 test kit tests the hardness level as mg/L (ppm) calcium carbonate, via an EDTA (ethylene-diamine-tetraacetic acid) titration. Range (0.0-30.0 mg/L) (0-300 mg/L).
During testing, when colour change is achieved, under careful conditions - usually using a burette – the reagent is added, drop by drop, until the solution turns to the colour required. The user will then count how many drops of reagent were used to achieve complete colour change. The number of drops used will determine the chemical concentration and results can be found in the manual included.
Water hardness has traditionally been defined as the capacity of water to precipitate soap. The ionic species in the water causing the precipitation was later found to be primarily calcium and magnesium. In the present, therefore, water hardness is actually a quantitative measure of these ions in the water sample. It is also now known that certain other ion species, such as iron, zinc and manganese, contribute to the overall water hardness. The measure and subsequent control of water hardness is essential to prevent scaling and clogging in water pipes.
The HI-3812 test kit is supplied with the following:
- 30 mL hardness buffer
- 10 mL calmagite indicator
- 120 mL EDTA solution
- 20 mL plastic beaker with cap and 50 mL plastic beaker with cap
- 1 mL syringe with tip