Color change chemistry projects are among the most interesting and entertaining science experiments. Color change chemical reactions visually indicate chemical changes in matter. They illustrate pH changes, acid-base reactions, oxidation-reduction, and other key chemistry concepts. Other projects change color due to conformation changes, light emission, and simply mixing colors. There’s a color change chemistry project perfect for any occasion.
Here is a collection of color change projects.
Is Color Change a Chemical Change?
Color change often indicates a chemical change or chemical reaction, but sometimes colors change without altering the composition of a substance. For example, mixing blue and yellow food coloring makes a green liquid, but no chemical change occurs.
Color Change Chemical Reactions
These reactions are chemical changes. They include acid-base reactions, redox reactions, and precipitate formation.
- Briggs-Rauscher Oscillating Clock: A solution oscillates between colorless, amber, and blue in this classic chemistry demonstration.
- Blue Bottle Chemical Reaction: In this project, a blue liquid turns colorless before turning blue again.
- Water to Wine to Milk to Beer: Pour liquid from one glass to another and watch it change into what looks like water, wine, milk, and finally beer.
- Gatorade and Drain Cleaner: This variation of the blue bottle demonstration uses Gatorade and drain cleaner instead of chemicals from a lab. The colors you get depend on the products you choose.
- Red Cabbage Juice pH Indicator: Cabbage juice changes color depending on a liquid’s pH. The color change covers the entire rainbow.
- Fake Blood Chemical Reaction: Reacting an iron(III) solution and potassium thiocyanate solution makes the iron thiocyanate complex, which resembles fake blood.
- Color Change Violets: Change the color of violets or other flowers using household ammonia.
- Color Changing Chemical Volcano: This chemical volcano erupts lava that changes colors from purple to orange.
- Bubbles That Change Colors: These soap bubbles change colors using pH indicators.
- Disappearing Ink: Acid-base chemistry makes colored “ink” disappear as it dries and reappear using household ammonia.
- Color Change Liquid Thermometer: Tell the temperature by whether the liquid is pink or blue.
- Color-Changing Chameleon Eggs: This edible color change chemistry project changes the color of gelatin spheres, depending on the pH of the liquid surrounding them.
- Easy Color Changing Drinks: Turn a soft drink or cocktail into a color change chemistry project without making it taste bad.
- Color Changing Crystals: These crystals spontaneously change color due to a slow chemical reaction within them.
Holiday Color Change Chemistry Projects
These chemical reactions involve colors associated with holidays and other events.
- Vanishing Valentine: A pink solution turns colorless as the oxidation state of its chemicals change.
- Hot and Cold Valentine: A pH indicator changes liquid from pink to colorless. A temperature change shifts the equilibrium between a normal and ionized form of a molecule, changing the solution pH and color.
- Water Into Wine or Water Into Blood: A clear liquid turns red. Use this color change chemistry project for either Easter or Halloween.
- Old Nassau or Halloween Reaction: A clear liquid turns orange and then black.
- Bleeding Paper: Goldenrod paper starts out golden yellow and turns blood red when you write your message.
- Christmas Chemistry Demonstration: This clock reaction is perfect for the winter holidays, as the liquid changes from green to red.
- Poinsettia pH Indicator: Extract pH indicator from a poinsettia plant and see test liquids to see if they turn the indicator red or green.
- Olympic Rings Demonstration: Pour clear liquid into five glasses and watch it turn the colors of the Olympic rings.
Combustion is a chemical reaction and thus an example of a chemical change. However, the reason flames change color in these projects is because of light emission. Heating colorants excites their electrons. Photons released as electrons return to more stable energy states cause the color change.
- Colored Fire: Make a rainbow of colored flames using common chemicals.
- Colored Fire Pinecones: Use colorants on ordinary pinecones to spice up your campfire.
- Rainbow Flames Jack o’ Lantern: Instead of illuminating your pumpkin with a boring candle, make a rainbow of colored flames.
More Color Change Chemistry Projects
These colorful chemistry projects don’t necessarily involve chemical reactions. Other reasons for color changes include alterations in molecule shape, mixing colors, and scattering light.
- Rainbow Roses: Turn a white rose into a rainbow use. With a little know-how, change black roses into rainbows, too.
- Copper, Silver, and Gold Pennies: Change the chemical composition of coins and watch their colors change, too.
- Change Egg Yolk Color: Color egg whites using food coloring. Coloring egg yolks is trickier because the yolks are oil-based rather than water-based.
- Change Urine Color: It’s easy to change urine color. You may have done it accidentally once or twice!
- Make Rainbow Paper: Coat paper with a thin film that shows the colors of the rainbow.
- Thermal Nail Polish: Thermal nail polish changes color according to temperature. See how it works and make it yourself.