Have you ever mixed copper sulfate-a blue liquid-with different types of metals to see how they react to each other? This past Saturday at our GEM (Girls Engaged in Making) Workshop we did exactly that! Taking pieces of tin, lead, aluminum, magnesium, zinc, copper, and even some steel wool to see how they react with copper sulfate. The girls had to look at the different characteristics of a chemical reaction; including color change, steam, bubbling, and even products of the reaction. Once the different reactions occurred, we asked the girls to sort out the test tubes from "most reacted" to "least reacted" using their own observations of the different reactions. In the end, they assumed that magnesium reacted with copper sulfate the most due to the color change in the liquid and solid, and that copper reacted with the copper sulfate the least as nothing changed within the test tube. Since nothing changed, we asked the girls why they thought this occurred, and they said that "..they are made of the same thing, copper, so they don't react". The copper atoms did in fact not react, instead they just bumped against each other and recognized that they were made of the same material.
We also used molds from our previous Polymer GEM Workshop to create metal objects! From butterflies to fingers, we used kinetic sand to create the mold that would soon hold melted metal. The girls got to pick a few molds to create, and if it didn't turn out the way they wanted them to look, thankfully all we had to do was reheat the metal and pour it into a new mold. The girls observed that the side facing the sand was smooth while the metal on the side poured onto the sand was not smooth. We assumed that this was because the sand made the metal form to the mold and smooth out, while the metal on top was left to move as it wanted before solidifying. Pictured above are some of the metal objects made that day. The butterfly held all the patterns of the polymer mold used!
For our last experiment, we tested different materials to see how they reacted with steel wool. The materials included hydrogen peroxide, iodized salt, non-iodized salt, baking soda, and water. We set up different cups (labelled 1-6) that had varying mixtures of the materials present. We set up the experiment in the beginning of the workshop and then let them sit until the very end. Cup 4, pictured above, reacted quickly and actually produced smoke that rose while the reaction occurred. The mixture in cup 4 included hydrogen peroxide, salt, iodized salt, and water. After looking at the different cups and how they reacted, we decided to put together all of the materials to see what would happen. Adding baking soda, hydrogen peroxide, salt, baking soda, and water together was an experiment made only for outside. Once mixed, the steel wool and materials started reacting after a few minutes. The reaction caused more smoke than cup 4 did, and it moved the steel wool so much that the liquids were mostly spilled out of the cup (pictured above). The girls learned that an increase in reactants causes an increase in products; the products being smoke, bubbling, and the oxidation of steel wool.
The girls always have a blast at our GEM Workshops. Please join us May 19th for our last GEM Workshop of this season! We'll be kicking off the next school year with new GEM Workshops, so watch out for more information about those.