Rock Candy (Creative Chemistry Experiments)

You will need:

1. cup of water
2. 3 cups of regular sugar
3. A tall glass
4. Pencil
5. Rough cotton string or yarn
6. Bowl for boiling water for the solution
7. Spoon
8. Food colour

Whether you are planning a birthday-party or a get-together with your friends, edible colourful rock candy is not only awesome to look at but also fun to eat. But, be prepared to make this in advance.

INSTRUCTIONS

1. Take long pieces of cotton string and tie them to your pencil. Place the pencil over the glass so that the piece of thread may hang till the bottom of the glass.
2. In a separate bowl, boil water on the gas. Be very careful while handling boiling water.
3. Add a few drops of food colour to the water.
4. Stir the sugar into the water, one spoon at a time, until every spoonful of sugar dissolves.
5. Stop adding sugar when the sugar starts settling at the bottom of the glass, even after a lot of stirring.
6. Slowly pour the water solution into the glass and let the string hang in the water.
7. Leave this sugar water solution aside for
   1-2 days.

RESULT

After a day or two, the sugar in the super saturated sugar solution can only stay dissolved till the water is hot. When the water starts to cool down, it cannot hold the sugar any more and the sugar ‘comes out’ of the solution, starting to crystalise.