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Vaporization (or vapo(u)risation) of an element or compound is a phase transition from the liquid phase to vapor. [1] There are two types of vaporization: evaporation and boiling. Evaporation is a surface phenomenon, whereas boiling is a bulk phenomenon (a phenomenon in which the whole object or substance is involved in the process).
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.
where P 1, P 2 are the vapor pressures at temperatures T 1, T 2 respectively, ΔH vap is the enthalpy of vaporization, and R is the universal gas constant. The rate of evaporation in an open system is related to the vapor pressure found in a closed system. If a liquid is heated, when the vapor pressure reaches the ambient pressure the liquid ...
The heat of vaporization is the energy required to transform a given quantity (a mol, kg, pound, etc.) of a substance from a liquid into a gas at a given pressure (often atmospheric pressure). Liquids may change to a vapor at temperatures below their boiling points through the process of evaporation.
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.
If the vapor then condenses to a liquid on a surface, then the vapor's latent energy absorbed during evaporation is released as the liquid's sensible heat onto the surface. The large value of the enthalpy of condensation of water vapor is the reason that steam is a far more effective heating medium than boiling water, and is more hazardous.
Water vapor, water vapour or aqueous vapor is the gaseous phase of water. It is one state of water within the hydrosphere. Water vapor can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Water vapor is transparent, like most constituents of the atmosphere. [1]
of vaporizationΔ vap H o +23.7 kJ/mol Std entropy change of vaporizationΔ vap S o? J/(mol·K) Solid properties Std enthalpy change of formation Δ f H o solid? kJ/mol Standard molar entropy S o solid? J/(mol K) Heat capacity c p? J/(mol K) Liquid properties Std enthalpy change of formation Δ f H o liquid: −483.5 kJ/mol Standard molar ...