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How to Make a Crystal on a String

Sugar crystals can be grown on a piece of string for a science experiment. The science experiment is used to teach children that sugar is made up of a lattice-like structure that creates a square. The string is soaked in sugar water and as the water evaporates, the sugar crystals are deposited onto the string. Sugar crystals take seven days to grow to the point where they are visible to the naked eye. You can make crystals on a string or you can grow them on a wooden Popsicle stick to make rock candy.

Things You'll Need

Water, 2 cups
White granulated sugar, 2 cups
Medium saucepan
Wooden spoon
Glass jar, 1 pint with lid
Oven mitts
Cotton string
Scissors
Waxed paper
Galvanized washer, 1-inch
Pencil

Instructions

- 1
  Add 2 cups water to a medium saucepan. Place the saucepan over medium-high heat. Once the water begins to boil, add 4 cups sugar to it. Continuously stir with a wooden spoon to make the sugar dissolve. Keep stirring until the sugar water comes to a boil.
- 2
  Put the glass jar on the stove. Remove the sugar water from heat and carefully pour it into the jar.
- 3
  Cut a piece of cotton string that is two thirds longer than the jar is tall. Cut a piece of waxed paper that is 1 inch longer than the cotton string. Tie one end of the string to the 1-inch galvanized washer and the other to the middle of a pencil.
- 4
  Insert the string, weight end first, into the sugar water and let it soak for two minutes. Remove the string and set it on the waxed paper. Straighten the string and let it dry for two days for the first initial "seed" of the sugar crystals to form or be deposited in the string fibers as the water evaporates. Cover the sugar water jar with a lid and set it aside.
- 5
  Set the sugar water jar in a safe location where it will not be disturbed and remove the lid. Insert the string, galvanize washer or anchored end first, into the sugar water. Set the pencil over the top of the jar and let the string hang straight down into the sugar water. Let the string sit and soak in the water for three weeks or until the water solution has dried up to get the biggest crystals possible.

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