Soxhlet Extraction of Coffee by 24h7k4

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									Soxhlet Extraction
    of Coffee
Coffee components are extracted into
 water through specially designed
            glassware.
                 Purpose
This simple experiment shows how a natural
 products are often extracted to concentrate
 soluble materials. A soxhlet extractor is
 specially designed for such extractions.
             Demonstration
This experiment shows the glassware setup
 required for a soxhlet extraction. Coffee is
 placed in the extraction “thimble”

The experiment shows how vaporization and
 condensation occur throughout the
 apparatus.
               Concepts
Extraction

Changes of State

Solubility
                  Extraction
Extractions are used when we want to separate
  substances. One way this can be done is by using
  a solvent in which a desired substance dissolves in
  and the undesired substance does not dissolve in.
  Coffee flavor from coffee grounds is a great
  example, as we leave behind the coffee grounds
  and obtain a great flavored morning beverage.
                  Changes of State
Evaporation
   -the phenomenon in which liquid molecules have enough energy to convert to
      the gaseous state without boiling
   -evaporation can occur at nearly any temperature: at any time some of the
      molecules in a liquid will have enough energy to escape into the air
Condensation
   -the phenomenon in which gas molecules lose energy required to be a gas and
      collect on a cool surface as a liquid
   -example, on a hot, humid summer day water condenses on the outside of a
      glass of ice water
   When molecules have lower energy their intermolecular attractions take hold
               Solubility
Solubility is a function of how well a substance
  dissolves in a solvent.
Coffee grounds are insoluble in water (nothing
  dissolves)
However, the flavorings in the coffee grounds are
  soluble in water (large amounts dissolve)—
  they are said to be the solute in the solution
In this demonstration, the soluble flavorings are
  what we want in our water.
Coffee is a solution: solutions include a solute
  (substance being dissolved) and a solvent
  (substance doing the dissolving)
               Conclusions
Using a soxhlet extractor is a way to separate
 soluble material from insoluble material
A soxhlet extractor repeatedly extracts with
 fresh solvent until it is stopped. Thus, it is
 possible to extract all of the soluble
 material, if given enough time. This would
 make for really strong coffee in this
 demonstration!
                 Comments
A soxhlet extraction is commonly used to extract
  compounds from plants to discover active
  compounds such as natural pharmaceuticals
Compounds extracted from plants or animal material
  are commonly called natural products
Some natural products are very useful chemical
  species for the production of drugs and ointments

								
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