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CHEM 433 - 11 / 17/ 11. VI. Mixtures: • Thermodynamic Description of Ionic Solutions ( 5.9 and beyond ) - mix G ° (i.e. what does it mean?) - mix G IDEAL (i.e. w / composition dependence) - mix G REAL ( w / activities)
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CHEM 433 - 11/17/11 VI. Mixtures: • Thermodynamic Description of Ionic Solutions (5.9 and beyond) - mixG° (i.e. what does it mean?) - mixGIDEAL(i.e. w/ composition dependence) - mixGREAL(w/ activities) • A 10-minute glance at phase diagrams for mixtures – “Azeotropes” READ: FINISH CHAPTER 5 Web site is up to date...
Two component systems: Temperature-Composition Diagrams (now p is fixed…) This is for an ideal mixture. A is more volatile (lower boiling) than B
Azeotrope: results when we have non-ideal mixtures (+ or – deviations from Raoult’s Law) At the “azotrope” - Liquid and Vapor have same composition • This is a “high-boiling” azeotrope: • +/– deviations ? • > or < 1 ? • A--B < or > A--A/B--B ?
Azeotropes: result when we have non-ideal mixtures (+ or – deviations from Raoult’s Law) This system exhibits “boiling point depression”! • This is a “low-boiling” azeotrope: • +/– deviations ? • > or < 1 ? • A--B < or > A--A/B--B ?