Question regarding the fact that positive deviation solutions have the lowest azeotropes.
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Regarding positive deviation solutions, the book states that they are solutions with the lowest azeotopic point, but positive deviation refers to a situation in which the equilibrium partial pressures of the components in a solution are higher than those predicted by Raoult’s law. If the partial pressures of each component are high, then the total pressure will be high. Since it is a equilibrium partial pressure, the saturated vapor pressure should be high, which means the boiling point will be higher. The minimum azeotrope temperature is when the boiling point of the solution is lower than the boiling points of each individual component, that is, the boiling point is reduced. Isn’t this a contradiction? I can’t understand it for now; please give me some guidance, thanks!
An increase in saturated vapor pressure indicates that the boiling point has decreased. That is, the temperature at which the saturated vapor pressure reaches atmospheric pressure decreases