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...
With each subsequent test 5th graders perform on the mystery chemicals they're learning new properties about each substance. With the vinegar test, students quickly learned which chemicals reacted to the vinegar and which ones didn't. Those that did produced gas immediately, creating some oooooohs and aaaaaaahs that excited the whole room!
After multiple tests, fifth graders are summarizing their findings through drawings. Each of our tests revealed a new property about each of the mystery chemicals, some more specific than others. For example, observing the chemicals with our eyes may have told us that the chemicals were white and grainy, but our water mixture test may have told us that the chemical dissolves and can pass through a filter. Check out some of the sample work above. Way to go scientists!
Fifth graders are truly acting like scientists...wait, they ARE scientists!
The five mystery chemicals identities are still unknown at this time, and even though we combined them with drops of water, the mixtures didn't really tell us many distinguishable properties. Many were still sticky, gooey, and white. Some of the mixtures felt a little more grainy than others, but we still couldn't determine one from another distinctly. So after creating a class properties table for the five chemicals, we had an in depth discussion as scientists do. Students suggested that maybe the six drops of water they used wasn't enough and that we should add more. Since only one of the chemicals dissolved, then maybe adding more would dissolve more of the chemicals? So that began our series of tests today! We mixed each of the five unknown chemicals with 10 mL of water and stirred them for a total of a minute and a half. After letting them sit, we noticed that some "settled" more than others. We restirred them and sent them through filters to close out our lab, and we'll wait for tomorrow's results! Keep up the great work, scientists!
To kick off our Chemical Tests unit, students are digging deep into understanding that matter can have many, many properties. Students were given a mystery chemical and observed its properties inside a bag, outside of the bag, and then combined with water. We practiced safe science and started generating some great questions to helping us uncover what the mystery chemical could actually be!
Fifth graders have quite a bit of understanding in our initial discussion about chemicals. They know they can be solids and liquids, and when combined with other chemicals, they can make new "stuff." Many students have some misconceptions, though, in that all chemicals are dangerous. This is just not true!
We began our unit setting up a K-W (What we Know and What We Want to Know). Students have some great questions...and these will help drive our learning on our Driving Question Board. Our overall focus will be based on the question, "How can I identify mystery chemicals?" |
Mrs. BrinzaWe always practice safe science in our room. We wear goggles to protect our eyes, never touch anything that is unsafe, and keep the aisles clear so we can freely and safely move around the room. Archives
February 2016
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