vapour pressure


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Related to vapour pressure: saturated vapour pressure

vapour pressure

the pressure exerted by a vapour (gas) that is in equilibrium with its solid or liquid form. The term is particularly important in the diffusion of water vapour.see TRANSPIRATION.
References in periodicals archive ?
The adjustable parameters m and n are obtained by minimizing as objective function the sum of the quadratic average deviation from the literature values for the vapour pressure, from NIST Chemistry WebBook, and the second virial coefficient (Tillner-Roth, 1998):
The obtained values of m and n for the seven fluids are listed in Table 3 with the percent average absolute deviation, AAD, from the underlying vapour pressure, saturated liquid and vapour volume data and the average absolute deviation, errB, from the second virial coefficient data (Tillner-Roth, 1998).
However the vapour pressure is now less accurately predicted (Table 3).
The values of m, n and p for the set of eight low acentric factor fluids are listed in Table 4 together with the percent AAD from the underlying vapour pressure, saturated liquid and vapour volume data and errB, the average error on B.
6]) the AAD in respect to the vapour pressure is within 0.
The vapour pressure (Equation (7)) is found from the composition of the oil phase, which in turn is obtained from Equation (6).
The composition of the emulsion is given in Figure 4 demonstrating the evaporation path, depicted as compound fractions, not to be a straight line in the two-phase region, due to the changed vapour pressure during the evaporation.
The general information in Figure 4 about general trends is significant, but the results also leave noteworthy additional information, the most vital of which is the fact that the time of evaporation is a first-order linear function of water weight content, because of the constant water vapour pressure.
In the initial part of the evaporation, in the two-phase region, the fractions of linalool and surfactant are not linear functions of the water fraction, because the vapour pressure of linalool varies with the composition, while that of the water is constant.
Considering the features in Figure 6, the variation in the vapour pressure of linalool with the evaporated amount of the emulsion is obviously a factor of significance.