Objective
By the end of this lesson, you will be able to grow your own rock candy and understand the science behind the process.
Materials and Prep
- 1 cup of water
- 3 cups of sugar
- Clothespin or popsicle stick
- Cotton string or pipe cleaner
- Clothespin or clip
- Food coloring (optional)
- Measuring cup
- Heat-resistant container or glass jar
- Pencil or chopstick
- Scissors
- Plate or tray
- Plastic wrap or coffee filter
- Adult supervision
Before starting the lesson, make sure you have all the materials ready and ask for adult supervision if needed.
Activities
- Dissolve the sugar: In a heat-resistant container or glass jar, mix 1 cup of water with 3 cups of sugar. Stir until the sugar is completely dissolved. You can add a few drops of food coloring if you want to make colorful rock candy.
- Grow your rock candy: Attach a cotton string or pipe cleaner to a clothespin or clip. Dip the string or pipe cleaner into the sugar solution, making sure it is fully submerged. Remove it and let any excess solution drip off. Place the clothespin or clip on a plate or tray, and let it sit undisturbed for several days. Observe the formation of sugar crystals on the string or pipe cleaner as it grows into rock candy.
- Monitor and record: Check on your rock candy every day and record its progress. Measure the length of the crystals and note any changes in size, shape, or color.
- Enjoy your rock candy: Once the crystals have grown to your desired size, carefully remove them from the solution and let them dry. You can now enjoy your homemade rock candy!
Ninth Grade Talking Points
Rock candy is a type of crystalline candy made from sugar crystals.
When you dissolve sugar in water, the sugar molecules separate and spread out evenly in the solution.
By allowing the sugar solution to cool and evaporate slowly, the sugar molecules come together again and form solid crystals.
The cotton string or pipe cleaner provides a surface for the sugar crystals to attach and grow.
The longer you let the rock candy sit undisturbed, the larger the crystals will grow.
Recording the progress of your rock candy helps you observe how the crystals change over time.
Rock candy can be enjoyed as a sweet treat once it has dried.