Experiment: Growing Crystals When substances change from a
liquid or gas to a solid, they can form crystals. In a crystal
the molecules of the material lock together in a regular and
repeating pattern. If a crystal is allowed to grow undisturbed,
it will form regular shapes such as cubes, or hexagon columns.
The type of substance and how its molecules interlock determine
the shape of the crystal. You can grow your own crystals at
home. For this experiment you will need a plastic or paper cup,
sugar or salt (about a cup of either), and a pan for heating
water. If you want to make both sugar and salt crystals you will
need two cups. Note: The following experiment requires the
heating of water with a flame and should ONLY be done under
adult supervision. STEP 1 - Put a half a cup of tap water into
the pan. STEP 2 - Heat the water over a flame. If you are going
to make salt crystals you need only heat the water to around 140
degrees. If you are going to make sugar crystals, bring the
water up to boiling. STEP 3 -