Skittles Chromatography Lab Names (include everyone in your group)
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Candies like M&M's or Skittles have different colors because of the various dyes inside. We will figure out which candies have which dyes in this experiment. Using "Candy Chromatography " we will dissolve the dyes out using water and separate them with a salt solution.
Materials:
- Candies of Different Colors M&M or Skittles work Well
- Coffee Filters or Filter paper
- Tall Clear Glass or Jar
- Water
- Salt
- Pencil (no pens or markers)
- Scissors
- Ruler
- Toothpicks
- Aluminum Foil
- Empty 2 liter Bottle and Cap or beaker
Process For Candy Chromatography:
1) Cut the filter paper into 2, 3 x 3 inch square.
2) Take the pencil and draw a line ½ inch from one edge of the paper.
3) Plot six dots equally spaced along the line. Leave ¼ inch between the first and last dots and the edge of the paper.
4) Under the line label each dot for the colors of candy you ’re going to test. (Y for yellow, G for green,
BU for blue, BR for brown).
5) Make candy dye solutions. Cut a 10 x 6 piece of aluminum foil and lay it flat.
Put six drops of water spaced evenly along the foil. Drop one of each color of candy in the water drops (one color candy per one water drop). Let the candies soak in the water for a minute or two.
Turn the candy over to get the other side as well. The color will begin to come off the candy into the water solution. Remove the candy from solution.
6) Take a toothpick and dip it into one of the colored candy solutions on the foil. Get the tip of the toothpick wet. Next, gently touch the toothpick to the corresponding marked place one the filter paper (blue solution on the dot you marked BU for Blue on the filter paper). Be gentle, we need the dot to be small 1/16 inch or less. Repeat the process using a different toothpick for each color until

you have a small dot on each marked part of the filter paper.
7) Let the colored dots on your filter paper dry.
8) Repeat step 6 to get more color dye on each of your filter paper dots. You will need to do steps 6 and 7 a total of three times. Be patient!
9) Once you have completed step 8, fold the filter around a pencil and tape so that the colored dots are hanging down on the bottom.
10) Lets make a developing solution next. Measure and put ⅛ teaspoon of salt and 3 cups of water into the empty (and clean) 2 liter bottle. Screw on the lid. Shake until the salt is dissolved in the water making a solution. This is called a 1% salt solution.
11) Pour 1/4 inch of the salt solution into a tall glass. The level of the solution needs to be low enough so that when you put the filter paper inside the dots will initially be above the solution level.
Hold the filter paper with the dots at the bottom and set it in the glass with the salt solution.
12) The salt solution will start to climb up the paper using a process called capillary action.
13) The solution climbs up the filter paper and moves through the colored dots.
The colored dots begin to separate into different color bands. Notice that some candy colors were made from mixing several different dyes. These colors separate into different bands as they move up the filter paper. Dyes separate due to some dyes sticking more to the filter paper and others being more soluble in the solution. As a result the dyes climb will stop at different heights on the filter paper.
14) Once the solution gets about ½ inch from the top edge of the filter paper, remove it. Lay the paper out to dry.
15) Compare the spots from the different candies, noting similarities and differences. Record your results.
**Which candies contained mixtures of dyes?
**Which ones seem to have just one dye?
**Do similar colors from different candies travel up the paper the same distance?
The Science Behind Candy Chromatography
Chromatography is the collective term for a family of laboratory techniques for the separation of mixtures. It involves passing a mixture dissolved in a "mobile phase" through a stationary phase, which separates the substance to be measured from other molecules in the mixture and allows it to be isolated and viewed.

After lab questions:
**Do you think the pigments in green M&Ms and green Skittles are the same? How can you use paper chromatography to find the answer?
**Summarize how you would conduct an experiment to find this out using the steps of the scientific method you learned in class.