Differences between hard and soft water

After softening hard water it does not contain minerals anymore.

The rain water is an example of soft water, but then it comes in contact with the ground and percolates through the mineral rich soil and stone filters it reaches the ground and becomes hard water after dissolving minerals like calcium, magnesium, iron and other natural minerals. This is the water we get in out taps from the ground. So depending upon the mineral constitution of water we can divide it into : Hard water and Soft water.

Hard water

Water with high mineral content is addressed as Hard water. It has more amount of minerals like calcium, magnesium, iron etc. Usually calcium and magnesium is found is abundance in hard water. Hard water can be easily identified because it hardly forms any lather with soap. It leaves residue on the surface of the container when boiled. There is two bifurcations in hard water:

  • Temporary hardness. (Can be removed by boiling)
  • Permanent hardness. (Can not be removed by boiling)

Temporary hard water is due to presence of calcium bicarbonate and boiling converts the carbonate to insoluble carbonate which is left behind as a residue.Permanent hardened can be removed by adding sodium carbonate in the water, the calcium and magnesium ions react with sodium to form a insoluble precipitate. In ion exchange process, sodium ions swap places with the calcium ions. The result is water with sodium ions instead of calcium ions leaving no residue behind.

Hard water is not bad for health, if the minerals are not in excess. It's also gives a pleasant and distinct taste to the water. Consumption of hard water is associated with protective properties in cardiovascular diseases but there is lack of enough studies to prove this. Hard water is believed to cause eczema in humans. It is believed to be harmful for skin and hair.Hard water is not a good source for commercial purposes. It can stain clothes and utensils. The hard water is a problem for industries because it can block pipes, or rust the boilers etc. Hard water can reduce the age of industrial machines.

But it is important to understand that before consuming the mineral rich ground water, it is important to purify it. And there are now various water purifiers available which purifies the water without demineralising it.

Soft water

The water with low calcium and magnesium ions in it is referred to as soft water. It has more of sodium ions in it. All the naturally available water is soft water. Rain water, water from melted snow and distilled water are examples of soft water. This naturally occur if soft water then percolate through ground it becomes hard of varying degrees. The lack of minerals in soft water makes it less suitable for drinking. The taste of soft water is less palatable than hard water. Soft water forms good amount of lather when mixed with soap. The soft water is preferred over hard water in commercial purposes because it doesn't leave residue behind, which is very important for machines long working life.

What are the differences between hard and soft water?
Hard water facts Soft water facts
Increased mineral water content, mostly calcium and magnesium Low in minerals, mostly contains sodium
Forms less/hardly any lather with soap Forms good amount of lather with soap
It is when water percolates ground through lime stones and mineral rich earth It is mostly naturally accuring water, e.g. rain water or water after snow melts
It is good to consume mineral rich water, but when boiled or kept over a period of time, it leaves behind residue (clog pipes, stain cloth, damaged machinery, etc.) It is not good for health but it is very suitable for commercial use