Make Your Own Rock Candy

Experiments

What You Need:
  • A wooden skewer (you can also use a clean wooden chopstick)
  • A clothespin
  • Water - 1 cup 
  • Sugar - 2 to 3 cups
  • A tall narrow glass or jar
  • Ask a parent or adult to help you with this experiment
Method:
  • Clip the wooden skewer onto the clothespin so that it hangs down inside the glass and is about 1 inch from the bottom of the glass.
  • Pour the water into a pan and bring it to boil.
  • Pour about 1/4 cup of sugar into the boiling water, stirring it until it dissolves.
  • Keep adding sugar, stirring each time until it dissolves, until no more sugar will dissolve in the water. This will take time and patience because it will take longer for the sugar to dissolve each time. Once no more sugar dissolves, remove the pan from the heat and allow it to cool for at least 20 minutes.
  • Pour the sugar solution into the jar almost to the top. Then submerge the skewer into the glass, making sure that it is hanging straight down the middle without touching the sides.
  • Allow the jar to cool and put it in a place where it will not be disturbed.
  • You will see sugar crystals grow in the next 3 to 7 days.
Conclusion:

When you mix hot water and sugar till no more sugar can dissolve, you make a super saturated solution. This means that the water can only hold that much sugar when it is hot. As the water cools, the sugar "comes out" again as sugar crystals on your skewer. The skewer, and sometimes the glass itself, act as a 'seed' that the sugar crystals start to grow on. With some luck and patience, you will have a tasty scientific treat!