The definition of water hardness is the amount of calcium and magnesium dissolved in the water. Hard water contains a high percentage of dissolved minerals, primarily calcium and magnesium.
You can feel hard water when you wash your hands with soap. You may feel like there's a layer of soap residue left on your hands. Soap reacts with the calcium in hard water, causing a sticky residue on your hands. More soap or detergent is needed to clean things, whether your hands, hair, or laundry.
When using a dishwasher, you may notice spots or a film on glasses if the water is hard. When hard water is heated, such as in a home water heater, a hard deposit of calcium carbonate can form. This scale can shorten the life of equipment, increase water heating costs, reduce the efficiency of electric water heaters, and cause clogged pipes.
Also, mineral buildup will occur in your home coffee maker, which is why some people sometimes add vinegar (an acid) to the pot. The acidity of vinegar helps dissolve mineral particles by making them charged. These newly charged particles are attracted to the positive and negative charges in the water and can be easily washed away.
Hardness is caused by compounds of calcium, magnesium, and a variety of other minerals. General guidelines for water classification are: 0 to 60 mg/L (milligrams per liter) as calcium carbonate is classified as soft; 61 to 120 mg/L as moderately hard; 121 to 180 mg/L as hard; and over 180 mg/L as very hard.
This problem is most evident when using groundwater, which is a major source of hard water. As water moves through soil and rock, it dissolves small amounts of naturally occurring minerals and transports them into the groundwater supply. Water is an excellent solvent for calcium and magnesium, so if minerals are present in the soil around a water supply well, hard water may be delivered to homes.
Water hardness varies from region to region. In areas where water is relatively hard, factories may have to spend money on water treatment to soften it, as hard water can damage equipment. Hard water can also shorten the life of fabrics and clothing.
It also damages water pipes, as the prolonged movement of hard water through the pipe can lead to a buildup called plaque. Just as in the human body, where blood vessels can shrink in internal diameter due to cholesterol buildup, water pipes can gradually become blocked, resulting in less water movement through the pipe and lower water pressure.
Hard water is harmless to health, but its harmful effects begin with its inability to form foam when used with soap or toothpaste, which causes increased soap consumption and can lead to serious problems in industrial settings!
Calcium and magnesium salts precipitate with heat, leading to increased concentration. This reduces thermal conductivity in various thermal vessels. Heat becomes more difficult to reach the heated fluid, resulting in increased fuel consumption. This can lead to boiler explosions due to the formation of insulating layers that prevent cooling, causing temperatures to rise dangerously. This can also result from clogged boiler pipes, along with rust and metal corrosion problems.
When textile fibers are treated with soap, the salts that cause hardness react with the soap to form a lime soap that is insoluble in water. This soap deposits irregularly on fabrics and threads, thereby attracting dust particles. It also results in irregular dyeing due to the resistance of dye molecules to penetration into the deposited areas.
The presence of calcium and magnesium particles in the water causes a significant decrease in the spread of the dye when dyeing fibers, which affects the fastness of the dye.
