Week 15

 

Week 15: 

1.) What did you learn this week? This week in the lab, we revisited the baking soda experiment. We were tasked with posing a question that students could answer through this activity. The question that our group posed was, “Is the weight of the baking soda and vinegar the same before and after they are mixed together?” The conclusion that our group determined is that the weights might not be exactly the same, but they will be very close before and after. First, we weighed the baking soda and vinegar in the Dixie Cups, then we mixed them into a plastic container that was sitting on a scale without screwing on the lid. Before we mixed them, the baking soda and vinegar weighed 12.8 grams. After, they weighed about 12.6 grams. We hypothesized that it weighed less after because of the chemicals escaping through the form as gas. Next, we repeated the same process but screwed the lid on after mixing the baking soda and vinegar. Before, they weighed about 21 grams. After it weighed 20.6 grams, Similarly, we thought that some of the chemicals might have escaped as gas in the time that it took us to screw on the lid to cause the mixture to weigh less after the reaction. Overall, I thought that the experiment demonstrated that mixtures weigh about the same before and after a reaction due to their relatively constant weights. To improve the process, I think that we could use different containers to mix the ingredients in in the future that have a better seal to keep the gas from escaping the container.

4.) How Can I Apply What I Learned? I thought that the activity was very engaging and could be replicated very well in an elementary classroom. Students will obviously be very interested in the reaction that occurs; however, I think they will also be very curious about the consistency in the weights before and after the reaction. The activity was initially difficult for us to complete, but I think elementary students would have no problem completing it with a little more instructions. Additionally, I think it would be beneficial to use containers that are more airtight in order to prevent gas from escaping and keep the weights more consistent. This modification will demonstrate the point better for students. Overall, I really like the hands-on aspect of the activity and believe that it would be beneficial to complete it with real students.

5.) Remaining Question: A remaining question that I have from the activity is why the mixture gets colder after the baking soda and vinegar react. Because of the gas, I would assume that the particles would heat up or speed up in order to break out of the solid or liquid state into a gas. However, this is not case. I wonder if maybe the mixture heats up when the reaction occurs and cools after the gas is released. I still don’t know why it actually gets cooler, though.