distillation and chromatography. objectives separate the components of a solution using distillation...
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Objectives
• Separate the components of a solution using distillation and chromatography
• Determine physical or chemical properties which proves separation was successful
• Determine Vapor Temperature variations during the distillation.
What is Separation
• The division of chemical mixtures into its chemical components by physical means.
• A single substance that has no other substances mixing with it is called a PURE SUBSTANCE. If there is something else mixed with it, it is a mixture.
Why Separations
• Most Chemicals are natural products that must be separated into pure chemicals for use in industry or research.
How to Separate
• Separations are achieved through mostly physical means.
• All chemicals have different physical characteristics.
• The differences in the physical properties are exploited to separated different molecules.
Example Physical Properties
• Boiling point
• Melting point
• Charge state
• Partition Coefficient
• Vapor Pressure
• Solubility
Physical Properties of C2 Molecules
Chemical Name Formula Mw Mp Bp log Kow pKaEthanol C2-H6-O 46.07 -114.1 78.5 -0.31 15.9
Acetic acid C2-H4-O2 60.05 16.6 117.9 -0.17 4.76Aetaldehyde C2-H4-O 44.05 -123.5 21 13.57Ethylamine C2-H7-N 45.08 -81.2 16.6 -0.13 10.87
Types of Separations
• Re-crystallization• Selective Precipitation• Solvent extraction• Electrophoresis• Distillation
• Chromatography• Field Flow Fractions• Super Critical Fluid• Hyphenated methods
The Master
British biochemist Richard Synge won the 1952 Nobel Prize in chemistry. He developed partition chromatography, a technique for identifying and quantifying the component parts of such substances as proteins, carbohydrates, and nucleic acids.
Types of Chromatography
G as S o lid C o lu m n G as L iq u id C o lu m n
G as
H P L C
C olu m n P ap er Th in L ayer
L iq u id
C h rom atog rap h y
Types Of Adsorption Packings
• Paper• Cellulose• Starch• Sugars• Magnesium Silicate• Calcium Sulfate• Silicic Acid• Silica Gel
• Florisil• Magnesium Oxide• Aluminum Oxide• Activated charcoal • ODS• Synthetic packing
Distillation is…•The separation and
purification of a mixture of components based on the different volatilities of each component.
•The volatile components are vaporized, then condensed, and collected.
Volatility
Water is less volatile than ethanol because water’s intermolecular forces are
stronger than those of ethanol.
Modifications to Procedure
• 1 ml direct pipette with pump• Small plastic beaker for density determination• Dye Mixture• Plastic graduated dropper for food dye• Ice• Large beaker for Ice Bath• Chromatography Kit• 4 vials for each component isolated
Procedure modifications
• Prepare a solution containing 25 % V/V Ethanol Water Solution
• Volume of solution prepared should not exceed 25 % of volume of pot Flask
• Determine Volume by the following Equation• Volume of Pot Flask * .25 = Total Volume of
solution prepared• Using a Pipette and Balance determine the
density of the solution prepared
Chromatography Analysis
• Wet the column using eluent which is designated as the most polar
• Place the .5 ml of solution prepared into reservoir of Column Chromatography apparatus as demonstrated by Instructor
• Draw into column the solution• Add the polar eluent into the column until
one of the dyes can be isolated into the small vial provided
Chromatography continued
• Place the less polar eluent into the reservoir above the column. Draw the eluent into the column as instructed.
• Isolate the second dye and place into labeled vial
Distillation
• Using Logger pro determine the temperature which is most constant during the distillation. Do not allow the vapor temperature to exceed 90 degrees Celsius
• Test the combustibility of the solution prepared and the combustibility of the components isolated
• Determine the density of the original solution and density of the separated components.