On the first day of Christmas Science, my mommy made with me….Candy Chromatography!
I’m always looking for a great way to incorporate fun educational activities with what we’re doing, and the holidays are no exception! To that end, we’ve decided to do a feature on The Twelve Days of Science! Every day, I’ll be sharing a new holiday-themed science project that you can do with your kids! We’ll have Santa Sleigh races, we’ll light up Rudolph’s nose, we’ll make fossilized ornaments, and we’ll be growing our own ornament crystals! This is just some of the stuff we’ll be doing, we have so many great things coming up, I can’t wait to share them with you! Since today is the first of our Twelve Days of Science, here’s the first project!
Skittles or M&Ms
White coffee filter
Small cup or wide mouthed jar
Pipette or medicine dropper
Pour ¼ cup of water into your cup. Add ¼ tsp of salt and stir to thoroughly combine.
Cut a coffee filter into a flat 3”x3” square. On the bottom of your filter paper, ½ “ from the bottom, use your pencil to draw a line across the coffee filter paper. Draw five small circles, evenly spaced apart, across the line on the filter paper.
Cut a strip of aluminum foil into a strip that is 8” long and 3” wide. Flatten out any wrinkles, and draw five circles, evenly spaced apart from one another on the foil strip.
Using your pipette, place 2 drops of water onto each circle on the aluminum foil. Place one color of Skittles candy onto each drop of water, and allow it to sit there for approximately one minute, while the colored dye dissolves into the water on the foil.
Remove the Skittles from the foil and discard them. Using one toothpick for each color, dab several drops of each color onto one of the small circles on your filter paper. Make sure you only dab one color onto each circle.
Tape the top of your filter paper to your pencil. Lower the filter paper into the cup, so that the water is just barely touching the bottom of the filter paper. Make sure that the water is below the line you drew on your filter paper.
Rest the pencil over the top of the glass. Allow the filter paper to rest in the water for approximately 30 minutes. Watch as capillary action draws the water up the filter paper, carrying the colors with it! Over time, you should see the separation of colors in your candies as it crosses over the filter paper!
Chromatography is a way of separating a particular substance, and identifying its components as it travels along a path and is absorbed at different rates. You can think of it as a substance climbing a ladder, and different components stopping along the way. By the time you get to the end of the ladder, you have lots of individual pieces on the rungs that you can see and identify!
As your candy coating crosses the filter paper, some of the color molecules are deposited on the filter paper as it travels upwards to the top. Different molecules are deposited at different rates, leaving different shades and hues of color behind on its path!
Scientists can use chromatography to identify all sorts of things from blood samples, to what pen was used to write a letter, to what pollutants are in a body of water, or even what unidentified medications are made of!
Take It Further!
Try this experiment with different candies. Will the color reading of m&ms be the same as what you see with Skittles? What about Gobstoppers, Nerds, or other colorful candies? Devise an experiment with different candy coatings to see how they all stack up on the ladder of candy chromatography!