Antifreeze

Antifreeze is a freeze preventative used in internal combustion engines and other heat transfer applications such as HVAC chillers and solar water heaters. The purpose of antifreeze is to prevent a rigid enclosure from undergoing catastrophic deformation due to the expansion of water turning to ice. Most antifreeze products are chemical compounds added to water to reduce the freezing point of the mixture below the lowest temperature that the system is likely to encounter. Either the additive or the mixture may be referred to as antifreeze. Antifreeze is normally a colligative agent when mixed with water, enabling it to reduce freezing-point depression for a cold environment and also increase the boiling point of the water. A colligative agent is properly referred to as both antifreeze and anti-boil when used for both properties.