Water is the most essential substance needed for the existence of every organism. Water covers 70% of the earths surface and comprises 60% of the human body. It is needed for bodily function, agriculture, industries, entertainment, and hydroelectric power. Freshwater is not entirely pure. It must sometimes be treated due to pollution, bacteria, and unsafe levels of minerals. Its composition ranges from gases in the air two minerals and rocks and soils. Calcium and magnesium are the most abundant cat ions found in natural waters. These cat ions come from rocks like dolomite, gypsum, and limestone.
The presence of ions contributes to what is called water hardness. Water hardness refers to the exact concentration of these ions. Hard water has a high concentration of cat ions and and ions. Therefore, soft water has a low concentration of cat ions and and ions. Water hardness is measured in molarity, parts per million, milligrams per liter, and grains per gallon. Although water may contain many different minerals, the hardness is usually reported in milligrams per liter of calcium carbonate.
Water hardness is important to understand due to the complications it can cause when untreated. This can be important to understand when dealing with plumbing systems. Hard water can leave mineral deposits and thick white residue. This residue, also commonly known as scale, clogs pipes and creates buildup and plumbing fixtures. Prior understanding of water hardness may allow for saving money in the future by installing a water softening system. Scale results in replacing expensive equipment and dealing with energy inefficiencies. .
Water hardness can be determined by many techniques. Different methods are accurate to different degrees. A cheaper, yet less accurate technique is ethylenediaminetetracetic acid titration, also commonly known as EDTA. And expenses get more accurate technique is atomic absorption spectrophotometry, also commonly known as AA.
