Activity: Rock Candy Print

Rock CandyAh, the sweet taste of science at work! Create shimmering sugar crystals with an experiment that really rocks!

You’ll need:

– a piece of string
– tablespoon of granulated sugar
– a glass bead or other small object
– small jar
– 1/2 cup of very hot water
– a pencil

What to do:

1. Fill the jar with hot water and stir in a spoonful of sugar at a time until the sugar no longer dissolves.

2. Thread the string through the bead and tie a knot at its end. The bead will act as a weight.

3. Wrap the other end of the string around a pencil. Rest the pencil on the mouth of the jar and allow the bead to dangle in the sugar water. The bead should not touch the bottom of the jar.

4. Place the jar in a warm place and let the sugar water stand undisturbed for a week or more. After a few days, you might have to carefully break and remove the crust of sugar crystals at the top so that the water can continue evaporating.

What happens:

Cube-shaped sugar crystals form on the string — you’ve made rock candy!

Why this happens:

Water molecules move slowly up into the air as water vapor during the process of evaporation. As more and more water evaporates, sugar atoms draw close together, forming cube-shaped sugar crystals. And that’s just what you’ll see left behind on the string after the water is all gone!

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