How to Soften Hard Water?

Do you live in a place where the water is "hard"?  
It is easy to tell if you do, because a chalky layer, or scale, will usually build up inside your kettle.
This layer is often called lime or limescale.
Scientists call it calcium carbonate. 
It is left on the inside of the kettle when some types of hard water are boiled.

Water becomes hard when it soaks through chalk, limestone or dolomite rocks.

These are all relatively soft rocks, some of whose chemicals dissolve in the water.
When water is boiled, the dissolved substances change, leaving the solid calcium carbonate behind.

In many ways, hard water is a nuisance.
When you wash in hard water, it is difficult to work soap into a lather.
Instead, the soap makes an unpleasant layer of scum on the surface of the water.
Because hard water contains harmful minerals, it can also do harm to hot-water systems.
Unless special chemicals are added to the water, scale builds up in the hot-water tanks and pipes just as it does inside a kettle. In time, the hot-water pipes may become blocked.

How to soften hard water?

One simple way of making hard water softer is to add a small amount of washing soda.

The chemical name for washing soda is sodium carbonate.
It removes the minerals that make the water hard. This stops a film of scum from forming and allows lather to form in the water when soap is added.
One simple way of making hard water softer is to add a small amount of washing soda.
The chemical name for washing soda is sodium carbonate.
It removes the minerals that make the water hard.
This stops a film of scum from forming and allows lather to form in the water when soap is added.

How to test for hard water - Home test

Find out if you live in a hard or soft water area.
You will need:
a bowl of water soap
washing soda a spoon
1. Run some water into the bowl and wash your hands using soap.
Did it make plenty of lather quickly? 
If so, your water supply is soft.
2. If the soap left a film of scum on your hands instead of working into a lather, empty and rinse the bowl and refill it.
Add one spoonful of washing soda and stir with the spoon until it dissolves.
Now take the soap and wash your hands again.