SMMARTideas

SMMART SCIENCE II: SALT CRYSTAL SNOWFLAKES

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Snowflakes fall to the ground in 6-sided crystals. There are basically 6 different types of snow crystals: needles, columns, plates, column with capped plates, dendrites and star. To see pictures of these crystal shapes you can check out: http://snowflakebentley.com/snowflakes.htm

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You can find more information about the 6 different snow crystal shapes at:

http://www.its.caltech.edu/~atomic/snowcrystals/primer/primer.htm

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SALT CRYSTAL SNOWFLAKE:

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This activity gives you a great visual model of what a 6-sided Star Snowflake Crystal looks like.

(http://www.planet-science.com/newsletters/randomised/22/index.html#4)

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You will need:
1 cup boiling water in a pot
Salt
Pipe cleaners and cotton string
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· Dissolve ¼ cup salt in 1 cup of boiling water. You want to make sure there are salt crystals that do not dissolve that are sitting on the bottom of the pot. You are creating a supersaturated solution where the water cannot dissolve any more salt.

· Twist three pipe cleaners together to make a six-armed star.

· You need to tie cotton around one of the arms then suspend it in a jar full of a saturated solution of salt or sugar.

· Make sure that your star is fully immersed in the solution but not touching the bottom of the jar.

· Try adding food coloring to the solution if you’d like a colored star.

You can also use 3 cotton pieces of string, tied together in a knot in their middles. Wet the strings in the supersaturated solution. Fill the bowl with the supersaturated solution and drape each free end over the edge of the bowl in the shape of a star. Be sure to put a paper towel under the bowl for any drips. Leave the string alone for a few days and see what forms along the cotton arms.

Lisa