Ice, Ice Baby: Fifth Graders Study Water in Its Many Forms
In fifth grade science class, students have been learning about different states of water and the processes that change its state. In this piece, fifth grader Mia C. shares the experiments and projects that her class has been engaged in since last fall and into the winter months.
Coincidentally, the day we had our first snow back in November, we were doing an experiment to create frost by mixing ice and salt in a tin can. We learned earlier that lower temperatures could slow down the movement of molecules. As water vapor in the air cooled onto the surface of the tin can, condensation formed and froze because of the cold temperature. We created frost by the processes of condensation and freezing, resulting in the water going from gas, to liquid, then to solid, as we watched the snowfall outside! What we have yet to learn, is that the salt and ice mixture actually has a lower temperature than just ice itself.
Comparing Solid and Liquid Water
Why do potholes form in winter roads? We answered this question by exploring the solid and liquid form of water molecules. H2O stands for two hydrogen atoms and one oxygen atom. It has a special shape due to the charges on the atoms. To better understand the water molecule, we created models using styrofoam balls and toothpicks. We then connected the water molecules together just like they would when water freezes into a regular ice lattice. What we discovered is that there is something very special and hexagonal about ice, and that the same number of water molecules would take up more space in solid form than in liquid form because of the hexagonal structure. That is why water expands as it freezes on the roads in winter, creating potholes. It also could have been the reason why a pipe burst in the Idea Lab in January.
Creating Our Own Snowflakes with Maker Bots
After our study of the ice lattice, we turned our focus to design engineering. We explored the science of snowflakes, and had the opportunity to engineer our own. Snowflakes start out as little bits of pollen or a speck of dust. As temperature drops, water molecules get an atomic attraction that help them form a hexagonal structure called diamond dust. As more and more water molecules add on to this diamond dust, a six-sided, symmetrical figure is formed. Snowflakes are six-sided and symmetrical because there are six corners sticking out with which water molecules are most likely to land on. They are also unique because of the rarity of having the same conditions when water molecules add on to a snowflake. What we discovered, is how a little speck of dust can turn into a piece of art, with the requirements that it has to be six-sided; it is always symmetrical; and no two snowflakes are the same.
Now it was time for us to combine what we learned about the science of snowflakes into a snowflake-inspired STEAM project (STEAM stands for science, technology, engineering, art, and math). We used science experiments to learn about water molecules and the changes of state. We used technology by 3D-printing our snowflakes using the MakerBots and a software program called Tinkercad to create snowflakes that fit the scientific requirements. We used the engineering process of testing and evaluating to improve our Tinkercad models by 3D-printing preliminary models. We used art by creatively combining different shapes in Tinkercad. We also did Kirigami—an art form through paper cutting—to play around with snowflake designs. Then, we used angle measurements in math to make sure our six-sided snowflake are symmetrical throughout.