At the instant when the solidification starts, the temperature shoots back up to the solidification temperature. For instance, while you can have liquid water below 0°C, it will only make ice while exactly at 0°C.kelvin490 said:My question is, if supercooling is necessary, what is the meaning of "equilibrium" solidification (or melting) temperature (e.g. 0oC for water)?
You can have any proportion of liquid and solid, in constant equilibrium, when exactly at the temperature of the phase transition. To actually convert liquid water to ice, additional heat must be extracted from the water. Usually, the liquid will exchanging heat with an environment below the transition temperature (such as a freezer at -18°C).kelvin490 said:Another question is, at precisely equilibrium temperature, will liquid becomes a mixture of solid and liquid or nothing will change? Some may say solid and liquid co-exist but what is the driving force if it is not energetically favorable for either side at exact equilibrium temperature? What determines the portion of liquid and solid at this temperature if they really co-exist?
Supercooling is a phenomenon in which a liquid is cooled below its freezing point without solidifying. This can occur when the liquid is not disturbed and does not contain any impurities or nucleation points, which are needed for ice crystals to form.
Supercooling can be achieved by rapidly cooling a liquid or by reducing its pressure. It can also occur naturally in some substances, such as water at high altitudes.
Supercooling has several practical applications, such as preserving biological samples, storing perishable food items, and creating specialized materials with unique properties.
The main risk of supercooling is that the liquid may rapidly solidify if disturbed or if a nucleation point is introduced. This can cause the liquid to freeze suddenly and potentially damage equipment or containers.
No, not all liquids can be supercooled. Liquids with high impurities or those that are highly viscous are less likely to supercool. Additionally, some substances have a lower supercooling limit, meaning they cannot be cooled below a certain temperature before solidifying.