Fifth graders are summarizing all their work using the Claim-Evidence-Reasoning (CER) model. When scientists state claims, they answer a given question, so fifth graders were answering the question, "What are the mystery chemicals' identities?"
They had to use at least two pieces of evidence in determining the identity of the mystery chemicals and then use that evidence in support of the information presented to them on the chemical information sheet.
Check out some of their work!
This week, students used the evidence they gathered from all their tests to determine the identities of the mystery chemicals. Students were provided with a chemicals information sheet, and they used the Claim-Evidence-Reasoning model to determine which chemical was sugar, baking soda, alum, talc, and cornstarch. Check out their awesome work!
What happens when you place red cabbage juice (a natural indicator for acidic, alkaline, and neutral substances) on various chemicals? THIS! We saw a wide range of color changes from the initial color of the red cabbage juice, suggesting that each of our substances reacted with the indicator in a different way.
So after the vinegar test, we learned a new property about some of the chemicals. Some of the chemicals reacted to vinegar and created a gas. With iodine at our fingertips, students suggested to use iodine to see if it revealed any new properties to us! Check out this picture to see the results!
Notice the orange chemical's reaction? It turned blackish/blue when exposed to iodine, while the others remained rusty brown in color. I wonder what this means about the chemicals' identities...