Today's experiment showed what happens when we mix together acetic acid and sodium bicarbonate - carbon dioxide (CO2) forms! We've done this in the past using the mini-volcanoes but today we trapped the CO2 in a bag. We measured the circumference and recorded our data.
We have been using an acid-base indicator - cabbage juice! - to explore properties of solids and liquids. Red cabbage juice actually changes color depending upon pH - bright pink in acids, blue/green in bases. After completing an entire unit on cabbage chemistry, the 4th graders started working on the lab entitled "Mystery Powders". My awesome chemists have to figure out how to tell t identical looking powders apart by using chemistry along with good scientific observations. Here they are at work in the lab!
