In cold countries, people add a little ethyl alcohol (also known as ethanol) to the water before putting it in the radiators of cars to prevent the water from freezing in extremely low temperatures. This practice is often referred to as "winterizing" the car's cooling system.
Ethanol has a lower freezing point than water, and when it's mixed with water, it lowers the overall freezing point of the mixture. By adding a small amount of ethyl alcohol to the water in the radiator, it reduces the risk of the coolant freezing solid during very cold weather.
When the coolant in the radiator freezes, it can expand and cause damage to the radiator or other components of the cooling system. If the coolant freezes, it can also prevent proper circulation of the coolant, leading to engine overheating and potential damage.
It's important to note that modern cars typically use a mixture of water and antifreeze (usually ethylene glycol-based) as coolant, which provides better freeze protection and helps prevent corrosion and overheating. This coolant mixture is often referred to as "antifreeze" because it contains additives that protect the engine from both freezing and boiling at high temperatures.
In regions with extremely cold temperatures, it's essential to ensure that the coolant mixture in the car's radiator is appropriate for the climate to avoid any potential issues related to freezing or overheating. If you're unsure about what type of coolant to use or how to properly winterize your car, it's best to consult the car's owner's manual or seek advice from a qualified mechanic.