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
- Water
- Sugar
- String
- Clothespin or pencil
- Clean glass jar
- Food coloring (optional)
- Measuring cup and spoons
- Parental supervision
Before starting the lesson, make sure you have all the materials ready and ask for parental supervision during the activity.
Activities
- Prepare the sugar solution by dissolving 1 cup of sugar in 1 cup of boiling water. Stir until the sugar is completely dissolved. Let it cool.
- Cut a piece of string long enough to hang into the jar with a little extra length to attach to a clothespin or pencil.
- Dip the string into the sugar solution and roll it in some extra sugar. Let it dry for a few minutes.
- Attach the clothespin or pencil to the top of the jar and suspend the sugar-coated string into the jar, making sure it doesn't touch the sides or bottom.
- Place the jar in a cool and undisturbed location, away from direct sunlight, and let it sit for about a week or until you see crystals forming on the string.
- Observe and document the changes in the jar daily. Take pictures or draw diagrams to track the progress.
- Once the rock candy has grown to your desired size, carefully remove it from the jar, let it dry, and enjoy your homemade treat!
Ninth Grade Talking Points
- "Rock candy is a type of crystallized sugar that forms when a supersaturated sugar solution cools down."
- "Supersaturation occurs when you dissolve more sugar in a liquid than it can normally hold at a given temperature."
- "When the sugar solution cools, the excess sugar molecules start to come together and form crystals on a surface, such as the string in our experiment."
- "The crystals grow over time as more sugar molecules join the existing crystals."
- "The shape and size of the crystals depend on various factors, including the temperature, concentration of the sugar solution, and the presence of impurities."
- "By controlling these factors, you can manipulate the growth of the crystals and create different shapes and sizes of rock candy."
- "The slower the cooling process, the larger and more defined the crystals will be."
- "Rock candy is a fun and tasty way to explore the science of crystallization!"