Why we add coolent in the radiator of car ?

How does a radiator of car works?


We all are familiar with the coolent that is normally used in radiators but many of us will admit that they don’t know how it works.

Well, being a chemistry geek here I will discuss how it works.

Ethylene glycol is the liquid that is widely used in the cooling system of various engines.

If we see back in the history ethylene  glycol discovered by French Chemist Charles Adolphe Wurtz in 1856.


And it was used in automotive engineering in 1926 during world War II . From then it is used in various vehicles.

Now coming to the question how it works?

The radiator of car is a system of copper pipes in which the coolent is circulated. It radiates the heat of engine outside .


Water boils at 100 degree Celsius and freezes at 0 degree Celsius. In the hilly areas or in the cold areas where the temperature drops near to zero or sub zero levels , the  water used to get frozen in the car radiator. As we know the ice occupies more space than that of liquid water, and it could crack the pipes of radiator and thus will damage the radiator and it would ultimately overheat the engine and will seize it.

Now if we add ethylene glycol in water to add in cooler to add in radiator it will increase the the boiling point of water beard hundred degree and also decrease the freezing point of water beyond the the zero degree. Now now is the car is parked in cold area for sub zero level areas the coolant mixture or the antifreeze mixture will not freeze and remain in the liquid state and in this case it will work properly.

Is it also increase the boiling point of water it will also prevent the overheating of water for simply the term boil over which is used in the mechanical language.

Simply it increases the melting and boiling point range of the water and keep it liquid in cold as well as hot weather.

Happy motoring

Published by Ankush Sharma

I am M.Sc (chemistry ) from Punjabi University Patiala. I am a science teacher with expertise in chemistry, with 8 years of experience in teaching. Writing and blogging is my hobby, I write whenever I am free. I am constantly working on creating a new and easy way of learning the tough things in an effective way. I am constantly working to make authentic and reliable information to be shared with my students and widen the horizons of knowledge.

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