Are you a candy lover? Have you heard of rock candy? It's those delicious colored sugar crystals on a stick!
What if you could use science to make your own rock candy? That's just what we'll do in this month's 20 Minute Lab!
Note: Setting up the lab will only take about 20 minutes, but you'll have to wait about a day to see the first crystals, and a few days to get a store-quality hunk of candy!
Notes: You can make as much or little as you like - as long you use a 3-to-1 ratio of sugar to water. It's important to have enough liquid to fill your jars.
You can also use string (attached to a stick or pen) instead of skewers.
If you don't see any sugar crystals on your skewer, try again and make sure that:
1) The skewer was fully dry before submerging (the skewer in the red jar was not dry enough, all the sugar fell off and dissolved right away!)
2) the solution is completely saturated with sugar, and
3) the solution cools down enough before the skewers are added.
Your delicious rock candy is actually a beautiful crystal. Crystals form when molecules fit together in an organized, repeating pattern.
The process of crystallization is when molecules transition from randomness to uniformity!
There are many different types of crystals found in nature, but crystals are generally formed in three ways:
Growing crystals from hot water:
By heating the water, you were able to dissolve more sugar than you could at room temperature. Hot water molecules are farther apart so they have more space to hold the sugar. This extra capacity for dissolving is called a supersaturated solution.
As the solution cooled, the water molecules moved closer together, so sugar came out of the solution (out of being dissolved) and began to form on the skewer in crystal form.
The sugar that you rolled onto the skewers themselves acts as a kind of 'seed', a starting place for the crystals to latch onto and grow. (If you used string, the string itself is fibrous enough to serve as the starting place for the crystals to grow.)
The size and shape of the crystals depends on how fast the solution cools. When solutions cool fast, you get smaller crystals because they have less time to organize. Slow-cooling solutions tend to form larger crystals.SHARE WITH US!
Let us know how your experiments turned out! Share your photos and results with us on Facebook, Twitter, Instagram, or send us an email to email@example.com. We love getting your messages!
For more exciting experiments, check out our Yellow Scope science kits on the Shop tab of our website!