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Evaporation is a phase transition from the liquid phase to vapor (a state of substance below critical temperature) that occurs at temperatures below the boiling temperature at a given pressure. Evaporation occurs on the surface. Evaporation only occurs when the partial pressure of vapor of a substance is less than the equilibrium vapor pressure ...
Boiling or ebullition is the rapid phase transition from liquid to gas or vapour; the reverse of boiling is condensation. Boiling occurs when a liquid is heated to its boiling point , so that the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.
Evaporation is an essential part of the water cycle. The sun (solar energy) drives evaporation of water from oceans, lakes, moisture in the soil, and other sources of water. In hydrology, evaporation and transpiration (which involves evaporation within plant stomata) are collectively termed evapotranspiration. Evaporation of water occurs when ...
Water boiling at 99.3 °C (210.8 °F) at 215 m (705 ft) elevation. The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid [1] [2] and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding environmental pressure.
Temperature-dependency of the heats of vaporization for water, methanol, benzene, and acetone. In thermodynamics, the enthalpy of vaporization (symbol ∆H vap), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy that must be added to a liquid substance to transform a quantity of that substance into a gas.
The difference in volatility between water and ethanol has long been used to produce concentrated alcoholic beverages (many of these are referred to as "liquors"). In order to increase the concentration of ethanol in the product, beverage makers would heat the initial alcohol mixture to a temperature where most of the ethanol vaporizes while ...
For clarification, a distinction between the two corresponding cases is needed. With reference to a phase diagram , the sublimation that occurs left of the solid-gas boundary, the triple point or the solid-liquid boundary (corresponding to evaporation in vaporization) may be called gradual sublimation ; and the substance sublimes gradually ...
Experimental measurement of vapor pressure is a simple procedure for common pressures between 1 and 200 kPa. [2] The most accurate results are obtained near the boiling point of the substance; measurements smaller than 1 kPa are subject to major errors. Procedures often consist of purifying the test substance, isolating it in a container ...