Last month I explained how to grow sugar crystals to make candy. This month, we are also going to grow crystals only we are going to make them look like snowflakes. Snowflakes are crystals of water. Since water needs to be kept cold to stay solid, you can’t really use water crystals to make things to keep inside.
You need to use other compounds, which are solid at room temperature (like sugar) to make things to keep. For this experiment, we are going to use borax. You can find borax in the laundry aisle of many supermarkets. One brand names is 20 Mule Team. Caution: This experiment uses boiling water which is very hot. Please be sure to have a responsible adult supervising. Also, be sure to wash your hands after working with borax and keep the snowflakes away from small children or pets that might try to eat them!
Materials:
1 cup boiling water
2-3 tablespoons borax
Shallow pan or jar
Pipe cleaners
1) Create your borax solution. Boil one cup of water. Little by little, stir the borax into the water (about a half tablespoon at a time). Keep stirring until no more borax will dissolve.
2) Create your snowflake form. Cut a pipe cleaner into three pieces and twist them together in the middle. If you want to grow your snowflake in a jar, make one piece longer so you can attach it to a pencil and hang it into the jar.
3) Put your snowflake form(s) into the jar or pan. Pour the borax solution on top. Put them in a place where you can check on them daily.
4) When your snowflakes have grown, take them out and let them dry. If you hang them near a sunny window, they will sparkle!
Things to Think About and Do
- Look at the crystals with a magnifying glass. Compare them to the borax powder you started with... do they look similar or different?
- Can you grow other kinds of snowflakes? You can try this same experiment with sugar, table salt or Epsom salts. Which grows the biggest snowflakes?
Growing Sugar Crystals
This is not an experiment—because you can eat the results. This is a cooking project which shows how science is part of our lives—even candy! Sugar is a solid. Each little grain or crystal of sugar is made up of lots of individual sugar molecules. The molecules are arranged in a very orderly fashion that gives sugar its shape. Rock candy is made of sugar crystals. The crystals grow bigger than the ones you find in a packet of sugar or the sugar you buy to make cookies. They’re easy to grow—just give it a try! Caution: The sugar/water solution is extremely hot. Please take care when mixing and pouring it.
Materials:
Remember—you’re going to eat the results—don’t use anything that you wouldn’t use for food preparation)
3 cups sugar
1 cup water
Heavy saucepan
Clean jars or tall glasses
Clean string, straw or popsicle stick
1) Get your crystal growing apparatus ready. You need to suspend your string into the container without it touching the sides or bottom. If you are using a string, you can tie it to a pencil and then lay the pencil across the top of the jar like shown in this image.
Wet your string and dip it into sugar so that a few crystals cling to the string. This will give your candy a place to start growing.
2) Put three cups of sugar in the pan and add 1 cup of water. It will seem like there is too much sugar/not enough water, but it will be ok! Put the pan on the stove and heat the sugar/water solution. Stir it gently. As the solution heats up, more and more sugar will dissolve. The solution will look cloudy. You want to heat it until the solution turns clear and starts to bubble. Be Very Careful—the solution is very hot. Let it cool for 5-10 minutes before proceeding.
3) Pour the solution into the jars. Be sure the string is not touching the sides or bottom. Growing crystals takes time because the crystals grow as the water evaporates. Cover the top with a paper towel or coffee filter to prevent dust from getting into the jar. Put the jar some place where it won’t be disturbed.
4) Check on your crystals every day. If a crust of crystals forms across the top of the jar, just remove it with a fork or spoon so water can continue to evaporate. If crystals form on the sides/bottom of the jar, pour the solution into a clean jar and place the string into the clean jar.
5) When your candy is big enough, you can take it out and eat it. If you want to save it, just let it dry and then store it in a closed container. It won’t spoil, but if you leave it out, it may attract bugs! Enjoy!
