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Acids, Bases, and Salts
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
Raoult’s Law states that when a nonvolatile solute is added to water or another solvent, forming a solution, the vapor pressure of the solvent is depressed. In other words, the vapor pressure of the solution is lower than the vapor pressure of the pure solvent. The vapor pressure of the solution is directly proportional to the mole fraction of the solvent multiplied by the vapor pressure of the pure solvent: Psoln=XsolventP°solvent
Phase and State Transitions and Transformations in Food Systems
Published in Dennis R. Heldman, Daryl B. Lund, Cristina M. Sabliov, Handbook of Food Engineering, 2018
The vapor pressure of water in a solution is always lower than the vapor pressure of pure water, that is, pA<pA0. Raoult’s law applies to dilute solutions, for example, dilute salt and sugar solutions, and it is an important relationship in estimating freezing and boiling temperatures of solutions.
Introduction
Published in Roger L. Wabeke, Air Contaminants and Industrial Hygiene Ventilation, 2018
Raoult’s law: The partial vapor pressure of each component of a solvent mixture equals its vapor pressure multiplied by its mole fraction in the liquid mixture, i.e., a solution’s vapor pressure is proportional to the mole fraction of its component solvents. Vo=298×V×P760×T
Polyethylene glycol and membrane processes applied to suction control in geotechnical osmotic testing
Published in International Journal of Geotechnical Engineering, 2022
Rick Vandoorne, Petrus J. Gräbe, Gerhard Heymann
An ideal solution is one in which the volume change of mixing and change in enthalpy during mixing are zero (Rudin 1999). In an ideal solution solute–solute, solvent–solvent and solute–solvent interactions are indistinguishable from one another, obeying Raoult’s law. Thus, ideality is generally approached for very dilute solutions and for solutions where the solvent and solute molecules are of a similar size and nature (Brown et al. 2018). For solutions of PEG as are relevant to this paper, Equation 2 deviates rapidly from reality as the concentration increases (Flory 1953; Manohar 1966; Money 1989). PEG molecules are much larger than water molecules and form strong hydrogen bonds in aqueous solution (Eliassi, Modarress, and Mansoori 1998). This compromises the assumptions of Raoult’s law. The presence of hydrogen bonds lowers the water activity more than would be calculated by Equation 2. Therefore, application of Van’t Hoff’s (1887) equation to determine the osmotic pressure of aqueous PEG will result in gross errors.
Moisture transmission behaviour of individual component and multi-layered fabric with sweat and pure water
Published in The Journal of The Textile Institute, 2018
Arunangshu Mukhopadhyay, Agya Preet, Vinay Midha
The above phenomena can be explained on the basis of Raoult’s law {Raoult’s law: Psolution = (χsolvent) (P°solvent)}; which states that the vapour pressure of a solvent above a solution is equal to the vapour pressure of the pure solvent at the same temperature scaled by the mole fraction of the solvent present. Thus, fabrics with sweat solution showed lower WVP (Figure 3(a)). Further it can be also noted that variability in the data of vapour permeability of pure water and sweat solution was quite large but in presence of fabrics, it reduces. This is due to the impact of boundary layer above the evaporative dish which is susceptible to be affected by wind speed and other environmental factors in the absence of fabric.