With the holidays rapidly approaching, kids will soon be out of school for their winter break. WITN's "resident scientists," Ms. Covey Denton, Elijah, Lydia and Bethany have three kid-friendly science craft experiments that can be done just about anywhere.
Instructions from Ms. Denton:
Be sure to watch the attached videos!
When you mix borax and water you create a suspension of borax. There should be enough particles to make the liquid cloudy. Very hot water can hold more dissolved borax than cold water. Hot water molecules are moving rapidly and are more spread out, that makes it easier for the borax to dissolve. When the mixture cools, the water molecules slow down and move closer together. That leaves less room for the borax and it begins to come out of the water solution.
As the borax settles out, it bonds with other borax. It does this on “nucleation sites” (cracks, bumps or a pipe cleaner) and begins to form crystals. The crystals come together on the bottom and sides of the container, on the string and on the pipe cleaner. The crystals continue to grow as the borax comes out of the water.
Science at Grandma's
Candy canes and starlight mints are made of sugar which dissolves in water. Hot water molecules dissolve things more quickly than cold water molecules because they are moving quickly and also have more space between them to dissolve the sugar molecules. The stripes are created by the different dyes. The dye changes the density slightly and will create stripes as it dissolves. Density is the measurement of how much “stuff” is packed into a measured space. Density = Mass (the stuff) ÷ Volume (a measured space). If you stir, the colors will all mix.
Epsom salt paintings. You want to dissolve some of grandma’s Epsom salts in some hot water. Just like the borax, the hot water dissolves more Epsom salts than cold water. Hot water also evaporates more quickly. As the water evaporates, it leaves the Epsom salts behind. The Epsom salts form small crystals as the water evaporates making crystal paintings.
Layered Elf Punch
Most of us understand density as floating and sinking—less dense objects will float on more dense objects (think vinegrettes, oil floats on top of the watery vinegar and you have to shake it before you use it). The same thing works with juices of different sugar contents. The more sugar that is dissolved in a drink, the more dense it is. So read your labels!
Start with the punch that has the most sugar. Using a pipette, dropper or a turkey baster, add the bottom layer of punch. Try and keep the sides of the cup clean and rinse the baster between layers. Adding layers is challenging! Its easy to rush and that just mixes the punch in the test tube instead of making layers. If you are gentle, you can get the layers to separate.
Ms. Denton is an award-winning science teacher at the Greenfield School in Wilson, NC. She was recently appointed to serve on a national education advisory board for "Infiniscope," which is a new virtual learning program funded by a NASA grant to teach kids about space.