Sublimatsioonil

Sublimatsioonil is a process in chemistry and physics where a substance transitions directly from the solid to the gas state, without passing through the liquid phase. This occurs when the vapor pressure of the solid exceeds the ambient pressure. Examples of substances that commonly undergo sublimation include dry ice (solid carbon dioxide), iodine, and naphthalene. The reverse process, where a gas transitions directly to a solid, is called deposition or desublimation.

The temperature and pressure conditions are crucial for sublimation to occur. At a given pressure, each substance has a specific sublimation point, which is the temperature at which it sublimes. For instance, dry ice sublimates at atmospheric pressure at -78.5 degrees Celsius. This property is utilized in various applications, such as freeze-drying, where water is removed from frozen materials by sublimation to preserve them. It is also used in printing technologies like dye-sublimation printing, where solid dyes are heated and turned into gas, which then permeates a material and solidifies. Understanding sublimation is important in fields ranging from materials science to atmospheric chemistry.