Candy Chromatography Lab Report

Candy Chromatography Lab

Paper chromatography is the ability to separate specific parts of a mixture, in order to identify its content. There are many forms of chromatography, but paper chromatography tends to work with substances such as dyes, inks, or any colored chemical. In the fields of biology, paper chromatography benefits police that need to test blood. It can also be used by chemists to test substances in their labs. Lastly, it can be used to identify compounds that may be in a plant substance.

The purpose for conducting this candy chromatography lab was to figure out which colors of skittles were not shown, by separating the pigment out. In this lab, the materials needed were four different colored skittles, rubbing alcohol, two coffee filters, two tall glasses or plastic cups, a pencil, ruler, tape, foil or paper plate, table salt, water, four toothpicks or cotton swabs, measuring cups/spoons, and a clean pitcher. The first step in conducting the lab was to cut the coffee filter. We had to cut two, 3 by 9 cm rectangles. Next, I dropped four drops of water onto a piece of foil, and did not allow them to touch. Then, I put one skittle of each color on the drop, and waited for the color to soak in. Then, I threw away the skittles. I then drew a line one cm from the edge of one end of one strip of paper using a pencil. Then, made four pencil dots along the line, 0.5 cm apart. Underneath the dot, I label the color of the candy you will test on that spot, using abbreviations. I used the colors red,

orange, green, and purple, so my labels were, “R, O, G, P.” Then, I made a prediction that the water was going to change to those colors. Using a toothpick, I dabbed a small amount of color onto the pencil dot for that color, and used a clean toothpick for each color. I then waited for the filter paper to dry, and added a little more color. Next, I had to make the salt solution. It was prepared by mixing together 1/8 teaspoon of salt and three cups of water in a clean pitcher. I stirred until it was completely dissolved. Then, I poured my solution into a clean glass. Then, I taped the strip of paper to a pencil until the strip was in the water and pencil laid across the top of the jar. Capillary action then drew the salt solution up into the paper, and it absorbed some of the color. As it passes through the dots, it will begin to separate the dyes. Once the water has a chance to absorb and go onto the paper, I let the strip dry, and repeated with all the colors, but this time, using alcohol.
After about twenty minutes had gone by waiting to see the colors from the salt water solution, they were starting to show up on the paper.

The red and blue were most visible and were near the purple. Blue and yellow were also seen on the green. The solution line made it to around 55-60%. After a few minutes had gone by waiting to see the results from the alcohol solution, the colors showed up well. It also took about twenty minutes, and the colors showed up

great.
During the investigation, I noticed that the alcohol solution made the colors stand out more. The colors were more clear and were not faded away, whereas in the water solution, the colors seemed slightly faded. Even though the alcohol solution provided a clearer version of the colors, the water solution percolated faster.
After comparing the results of the two solutions, the alcohol solution took longer than the water solution did. However, the alcohol solution provided a clearer picture. For the water solution, the green color made it furthest up the strip, and the red color stayed where it was. For the alcohol solution, the red solution spread the furthest up, and the green solution stayed still. The colors that did not spread stayed still, and were strong. The colors that spread, were diluted and weaker. Overall, I felt the lab was easy and did not take too long to complete. I made a mistake once by spilling the drop of water into the other, so next time, I would make sure to have a pipette, or something easier to make drops with. If I stopped the solution before it was done, It would have given us poorer results because it wouldn't have allowed time for the colors to soak in/ fade out.