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 Temporary Hardness of Water

In this article, we will learn about the temporary hardness of water. Temporary hardness can easily be removed by boiling the water.

There is a big difference between the temporary and permanent hardness of water. When you boil water, you can get rid of temporary hardness, but you can’t get rid of permanent hardness.

Water hardness can be thought of this way. This is how many total divalent ions there are in a given amount of water. Water has calcium ions, magnesium ions, and Fe2+ ions, all divalent ions that can be found in the water. The most common hard water causes are calcium and magnesium, but they aren’t the only ones. People use ppm per CaCO3 equivalents to measure how hard things are. Water hardness can be temporary or long-term, and it can be both. 

What is Temporary Hardness of Water?

For a short time, calcium hydrogen carbonate and magnesium hydrogen carbonate are blamed for making the rocks hard. CaCO3 or MgCO3 comes out of both species when heated and breaks down into their separate parts. It’s because you can use boiling water to get rid of the hardness for a short amount of time.

There are calcium and magnesium cations and carbonate and bicarbonate anions when minerals like calcium bicarbonate and magnesium bicarbonate break down in the water. A sample of water with many metal ions in it makes the water hard. Lime can also be added to water to make it less complicated (lime is calcium hydroxide). Lime softening is a process that adds lime to water.

What is the Permanent Hardness of Water?

Sulphates and chlorides of magnesium and calcium are to blame for the hardness that doesn’t go away quickly. People get sick if the water has calcium sulphate or calcium chloride and/or magnesium sulphate or magnesium chloride in it, and they get sick. This makes the water very hard for a long time. To say it another way: The hardness is made up of calcium hardness and magnesium hardness, so we can say it is the sum of both.

In hot water, these minerals don’t fall to the bottom of the water. Getting it soft by boiling will not change its hardness permanently. Ion-exchange columns can remove hard water that isn’t going away any time soon. Water softeners can also be used to remove it.

What is the Difference Between Temporary and Permanent Hardness of Water?

They make the skin a little hard for a short time. There are two types of hydrogen-carbonates: Ca (HCO3)2 and Mg (HCO3)2. Sulphates and chlorides of magnesium and calcium are tolame for the hardness that doesn’t go away quickly. 

There is a big difference between the temporary and permanent hardness of the water. You can boil the water to get rid of temporary hardness, but you can’t get rid of permanent hardness by burning it. It’s not enough to add a water softener or use an ion-exchange column to get rid of the hardness in water. Instead, we need to use another method to get rid of the hardness in the water.

Carbonate or Temporary Hardness

People who drink this kind of water have carbonate and bicarbonate ions to blame, for it is hard. It is also called “temporary hardness” because it comes out of water when we boil it.

When we boil water, the carbonate and bicarbonate ions in it break down, and the insoluble carbonate that isn’t in water separate out.

When you boil water, much calcium and magnesium carbonate come out of the water. People can get rid of calcium and magnesium ions from the water more quickly.

Example: CaCO3, MgCO3, Ca(HCO3)2, Mg(HCO3)2

Non-Carbonate or Permanent Hardness

Non Carbonate ions, like chloride and sulphur, are to blame for this type of water hardness. They cause it.

When you boil water, you can’t get rid of the hardness, called “permanent hardness.”

There are two ways to remove it from water: softening and demineralization.

Example: CaCl2, MgCl2, CaSO4, MgSO4


All living things need water to get their food and live in their environment. The food and dairy industries use a lot of water. Use water to make steam, clean plants, and equipment, condense vapours, sanitise, drink, and dispose of waste, among other things.

There is a good chance that hard and soft water are found together. Ca2+ and Mg2+ are the di-cations that make water hard. Calcium and magnesium carbonates and bicarbonates are the leading cause of the hardness that lasts for a time.

 When you boil water, you can quickly get it off. Sulphates and chlorides of calcium and magnesium in water make the water more acidic, which makes the water harder. This makes the water more acidic. Boiling water can’t get rid of it. It will take a lot of work to get rid of it. There are many ways to make water less complicated. Cold lime, Base exchange softening, Demineralizing (Deionizing) water supplies, Filtration, Reverse osmosis (RO) system, and chlorination methods are some of them.


Frequently Asked Questions

Get answers to the most common queries related to the JEE Examination Preparation.

What is the temporary and permanent hardness of water? How is it caused?

Ans : There are salts of magnesium and calcium in water that make it hard for a temporary. Some of ...Read full

What is the other name for temporary and permanent hardness?

Ans : Carbonate and noncarbonate hardness are also called these two types of hardness, but theyR...Read full

What causes temporary hardness?

Ans : The hardness that lasts for a temporary period comes from calcium hydrogen carbonate CaHCO...Read full

What is the reason for the permanent hardness of water?

Ans : Hard water is made when chlorides and sulphides of calcium and magnesium are dissolved in wat...Read full