Total water hardness is the measure of the calcium and magnesium contained in the water. These two elements combined form calcium carbonate. Our body needs calcium (Ca) and magnesium (Mg). In some countries, minimum levels of calcium are recommended (minimum calcium level is 20 mg/l). The main problem with a high total hardness level in the water is that deposits can form in the pipes and make them less efficient. If the water is too hard, it can also cause the effectiveness of soaps and detergents to decrease, and affect the taste of the water.
Material:
1 - sample of total hard water (800 mg/l) provided by the limit value of the province of Saskatchewan (VLRS)
2 - packs of test strips (with printed color charts)
3 - 10ml disposable beakers
Methodology:
Label the two beakers according to their respective contents.
Fill the beakers with 10 ml of water from the samples.
Immerse a test strip in the beaker containing the local water for 3 seconds.
Remove and immediately determine the closest color on the color chart. The color is stable for only one minute.
Record the results in mg/l (or parts per million).
Repeat for the sample of the Province of Saskatchewan Recommended Limit Value for Total Water Hardness (VLRS).
You need a colorimetric analyzer that uses solutions that will color the water depending on the degree of hardness. This mixture is then passed in front of a lamp which then determines the hardness value by colorimetric measurement.
