My 6th graders are working on changes of states of matter. When we do a lab activity, I usually write up all of the instructions for them. In this activity, because it was pretty simple, I explained the instructions and the students worked with their lab partners to write up the steps.
For this simple activity, each group gets an ice cube, a snack size Ziploc bag and an Alka Seltzer tablet. First students place the ice cube in the bag and seal the bag. I challenged students to see who could melt the ice cube quickest. Most students started by rubbing the bag between their hands and realized it was much quicker to stick the bag near the heater or run the bag under warm water.
After the ice cube was melted, I placed an Alka Seltzer tablet in the bag. Students QUICKLY zipped up the bag and made observations. After about a minute, the fizzing made the bag fully expand.
Students then wrote out the instructions and described the changes in states of matter that took place. We had a little bit of time left at the end of the period so the students brainstormed additional activities that we could try. Before the end of the period, we tried 3 tablets (the bag popped open), a crushed tablet (it dissolved super quick) and ice cubes mixed with water (the tablet took a long time to dissolve).
Click on the picture below to download the PDF.
Enjoy! Have an awesome weekend!