CHEM 235 Lecture Notes - Lecture 9: Fractional Distillation, Azeotrope, Potentiometer
Document Summary
Distillation : (1) heating a substance until it vaporizes, (2) condensing the resulting vapours by cooling, (3) collect . Wide separation between bp (50 c or more) if separating two or more volatile liquids at least one left behind in distillation flask) components must . Form an components of mixture so that liquid distills at constant temp/composition even though components have different bps e. g. ethanol and water @ 95% and 5%) Boiling point : when total vapour pressure = atmospheric pressure (constant for pure substance) For a liquid: (1) bp of neat liquid (2) refractive index (r. i. ) of the liquid. Physical constant depend on wavelength of light and temperature. 25 ml graduated cylinder thermowell (heating mantle) rheostat iron ring + wooden square refractometer. Caution. contact with strong oxidizing agents such as chromium trioxide or potassium permanganate may produce an explosion. May cause adverse reproductive and fetal effects. handle with care. flammable.
