evapor

Evapor is a rarely used English verb whose common form is evaporate. The related noun is evaporation, and related forms include evaporates, evaporating, and evaporated. In practice, most writers use evaporate in place of evapor, and evaporate is the standard infinitive. The term refers to the process by which a liquid changes into a vapor, primarily at the liquid’s surface.

Evaporation occurs when molecules at the surface gain enough energy to overcome intermolecular forces and escape into the surrounding gas. This can happen at temperatures below the liquid’s boiling point. The rate of evaporation depends on several factors: the vapor pressure of the liquid at the ambient temperature, the temperature difference between the liquid and its surroundings, the surface area of the liquid, air movement above the surface, ambient humidity, and the concentration of vapor in the surrounding air. Higher temperature, greater surface area, drier air, and lower ambient pressure all tend to accelerate evaporation.

It is distinct from boiling, which is rapid vaporization that occurs throughout the bulk of the liquid at its boiling point. Evaporation is a surface phenomenon and can proceed at any temperature below boiling.

Evaporation has wide natural and industrial relevance. In the natural world, it drives the water cycle from oceans and land. In industry, it is used in drying, concentration of solutions, solvent recovery, and desalination processes. Equipment that facilitates evaporation includes evaporators, which may use heat, vacuum, or reduced pressure to remove solvent by vaporization.