Chromatography
Search the web. Some interesting sites are listed below. Note that some of these sites go into much more depth than is reasonable for this course.
http://en.wikipedia.org/wiki/Chromatography http://ull.chemistry.uakron.edu/analytical/Chromatography/ http://orgchem.colorado.edu/hndbksupport/TLC/TLC.html this is for TLC – similar to paper http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/Chromatography_paper.html http://jchemed.chem.wisc.edu/JCESoft/Programs/CPL/Sample/modules/paprchrom/paprchromdesc.htm http://jchemed.chem.wisc.edu/JCESoft/Programs/CPL/Sample/modules/paprchrom/paprchromdesc.htm This site shows the colors of many of the food colorings and lakes http://www.dynemic.com/food%20colour.htm This site has colors and correct names for many of the colors. You can get the structures from the names with CRC or a good organic chemist. http://vm.cfsan.fda.gov/~lrd/colorfac.html this is a general site with information on food colorings – discusses difference between dyes and lakes
Procedure –
Extract the color from the candies
1. Label each of the beakers with one color of the candy.
2. Place one sample in each cup.
3. Put as few drops of water as possible (around 5) in each cup.
4. Stir carefully to extract as much color as possible without disturbing the white coating or the centre of the candy.
5. Remove the sample as soon as the white coating appears.
6. Add each sample in turn to its appropriate cup until as much color has been extracted as possible.
Note: Repeat the steps for each kind of candy. Be sure to include the color and kind of candy on your label.
Prepare chromatogram
1. Cut a piece of chromatography paper in half to form a rectangle with dimensions 10 cm x 20 cm.
2. Draw a line approximately 1 cm from the long edge of the paper with a pencil.
3. Mark dots along the pencil line approximately 1-1.5 cm apart and label as food dye colors yellow, green, blue, and red. Mark two additional dots for
http://en.wikipedia.org/wiki/Chromatography http://ull.chemistry.uakron.edu/analytical/Chromatography/ http://orgchem.colorado.edu/hndbksupport/TLC/TLC.html this is for TLC – similar to paper http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/Chromatography_paper.html http://jchemed.chem.wisc.edu/JCESoft/Programs/CPL/Sample/modules/paprchrom/paprchromdesc.htm http://jchemed.chem.wisc.edu/JCESoft/Programs/CPL/Sample/modules/paprchrom/paprchromdesc.htm This site shows the colors of many of the food colorings and lakes http://www.dynemic.com/food%20colour.htm This site has colors and correct names for many of the colors. You can get the structures from the names with CRC or a good organic chemist. http://vm.cfsan.fda.gov/~lrd/colorfac.html this is a general site with information on food colorings – discusses difference between dyes and lakes
Procedure –
Extract the color from the candies
1. Label each of the beakers with one color of the candy.
2. Place one sample in each cup.
3. Put as few drops of water as possible (around 5) in each cup.
4. Stir carefully to extract as much color as possible without disturbing the white coating or the centre of the candy.
5. Remove the sample as soon as the white coating appears.
6. Add each sample in turn to its appropriate cup until as much color has been extracted as possible.
Note: Repeat the steps for each kind of candy. Be sure to include the color and kind of candy on your label.
Prepare chromatogram
1. Cut a piece of chromatography paper in half to form a rectangle with dimensions 10 cm x 20 cm.
2. Draw a line approximately 1 cm from the long edge of the paper with a pencil.
3. Mark dots along the pencil line approximately 1-1.5 cm apart and label as food dye colors yellow, green, blue, and red. Mark two additional dots for