How does anti-freeze work??

Question

I know it prevents freezing but exactly how does it do this? If its a chemical reaction then how does it sustain it for very long?

Answer 1

Think about things this way.

Water is a common chemical compound. A chemical compound is simply 2 or more elements chemically combined.

Water we know freezes as 32 degree F. Water is a chemical usual called H20 and sometimes also HOH (Hydrogen Hydroxide)

Now you could use water to keep your car cool but in winter if the temperature drops to 32 or below the water freezes and the expansion due to freezing would crack your engine block. Not a good thing.

So, in order to protect the engine during the extreme in temperature another chemical compound is needed. One that will freeze at a lower temperature.

The most common way to do this is a combination of water and another chemical compound that has a much lower freezing point. Ethylene Glycol (C2H6O2) is commonly used.

So, it's not so much a chemical reaction.

It is just a chemical compound that has a lower freezing point.

Answer 2

This is due to a colligative property called Freezing point Depression. The general idea is if you add a solute to a pure solvent the freezing point of that solvent is reduced (lower temp is required to freeze it). This is becasue adding any solute to a pure liquid solvent lowers its vapor pressure. iF solid solvent (frozen crystals) and liquid solvent are to coexist they must have the same vapor pressure so if you drop antifreeze (solute) into a desired solvent then u lower its vapor pressure therefore for the solid (frozen crystals to develop) the freezing temp must be lowered also.

Answer 3

It is a liquid which freezes at a lower temperature. If you take water and add hyrogen peroxide to it, you will notice, the mixutre wll freeze only below -25 degrees celsius

Answer 4

http://auto.howstuffworks.com/cooling-system3.htm