Z used as a dry cleaning solvent in lieu of methylene

Info icon This preview shows pages 31–46. Sign up to view the full content.

View Full Document Right Arrow Icon
z Used as a dry cleaning solvent in lieu of methylene chloride (CH 2 Cl 2 ). z Used to extract caffeine from coffee beans. z Used to extract essential oils and natural products from organisms for pharmaceutical use.
Image of page 31

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Other Supercritical Fluids
Image of page 32
Example Problem z Predict what will happen to the following samples of CO 2 : z (a) Dry ice at –56 °C and 73 atm is suddenly placed in a vacuum chamber at the same temperature. z (b) Supercritical CO 2 at 20 °C is mixed with liquid N 2 at –196 °C. z (c) CO 2 gas at 130 °C and 40 atm is flash-cooled to –196 °C at 1 atm.
Image of page 33

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Phase Diagram of CO 2
Image of page 34
Example Problem z (a) The dry ice will instantaneously vaporize, potentially exploding the vacuum chamber if the rate of evacuation is not sufficient. z (b) This cannot be determined from the phase diagram given since the result of the reaction would result in a mixture. z (c) Deposition of dry ice
Image of page 35

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Solubility z To dissolve something means to take it from the solid state and put it into solution using a solvent. z In order for a solvent to be able to dissolve a solute (the substance dissolved), the solute must be soluble in the given solvent. z A solution is said to be saturated when the solvent has dissolved all the solute it can and some undissolved solute remains. z The molar solubility, s , of a substance is its molar concentration in a saturated solution.
Image of page 36