week 8: salty snowflakes

Want to make crystal snowflakes but without the borax for the younger folk? Try this (slightly different, but still cool) version.

Materials: 

• Construction paper (we recommend blue)
• Salt
• Hot water
• Spoon
• Paper plate
• Scissors

Directions:

1. We start with a fun little craft -- cutting paper snowflakes. Make sure your completed snowflake fits completely on the paper plate. If it is too large, refold it and trim the edges.
2. Place the snowflake flat and unfolded on the plate.
3. Add salt to the hot water and keep stirring. Stop adding salt when it is unable to fully dissolve in the water any longer.
4. Pour the hot, salty water on the snowflake until it is completely dampened. Do not oversaturate the snowflake; as long as there is water on the paper, it is fine.
5. Leave the snowflake overnight in a cool, dry place. Return the next morning for some "cool" results!

What's Going On?
Dissolving salt in hot water is different from dissolving it in room temperature or cold water; since water molecules in boiling water move faster and more freely, there is more space for the salt to dissolve.
As the salt water loses heat, these water molecules slow down and are more close together. It can no longer hold the amount of solution that it could when the water was boiling. This is what causes the crystals to form on the snowflake!