vapour pressure

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Related to vapour pressures: saturated vapor 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 vapour pressure of all samples was measured using the ASTM D5191 Dry Vapour Pressure Equivalent (DVPE) method.
The results of Figure 4 also show that year-to-year differences in gasoline vapour pressure (shown later in Figure 6) were not due to differences in ethanol content.
Figure 5 compares the vapour pressure of the Montreal E85 and gasoline samples with the minimum vapour pressure values specified for Class III and Class IV seasonal volatility fuel ethanol.
Despite the relatively long period the fuel remained in the tank, vapour pressure loss due to the evaporation of volatile components (referred to as fuel "weathering") was minimal.
Consequently, the vapour pressure along univariant G + A + V can be estimated from relationships between NaCl concentrations and transition temperatures gypsum-anhydrite obtained in CaS[O.
For the case of vapour pressure (uv) between 0[degrees]C and 150[degrees]C, a expression given by Eq.
11 predicts the vapour pressure of a sodium chloride solution with reasonable accuracy up to m= 3 mol/kg [H.
At 56[degrees]C this univariant give a saturation vapour pressure uv = 121,8 torr (16,24 kPa); associated with uvo = 124,6 torr (16,61 kPa).
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.
These results offer a comprehensible image of the variation of the emulsion compounds and the vapour pressure of the fragrance compound during evaporation.
The evaporation line equation is effortlessly obtained from these coordinates, but in the present contribution a continuation of the calculations for the two-phase range was instead chosen with the modification of a constant vapour pressure of the linalool, which approach offered a simple corollary that the calculations are correct.