All freshman Chemistry classes presented “Kitchen Chemistry” projects to demonstrate gas law concepts to their classmates. From “The Can Crusher,” to the classic “Mentos and Diet Coke,” Students in Alyssa McGarvey’s class used an online platform called VoiceThread to share their work. VoiceThread is used in classrooms to share their work and receive comments from other students and faculty members. Each part of the presentation and discussion is recorded and shared.
Groups uploaded their video presentations to the platform along with voice clips explaining their experiments. In one presentation, Evan Nord ’23 uploaded his video of the “Can Crusher” experiment. He filled an empty soda can with a half-ounce of water and then placed it on a hot stovetop until steam rose from the can. (All students were required to ask permission from an adult before performing their projects.) Once the steam was rising, Evan used tongs to flip the can into ice-cold water. The can immediately collapsed.
Next up, Billy Zhang ’23 and Orli Friedenberg ’23 explained real-life applications for this experiment.
“Some applications for this assignment are to test atmospheric pressure and what happens when you have a temperature difference at a much larger scale,” Billy said. “The information can be applied to make sure that technology securing air pressure inside planes can be equalized to maintain to ensure safety and making sure that submarine to go farther down to the ocean.”
Orli related this project to something on a smaller, possible more relatable scale–drinking soda out of a straw. “When you’re drinking through a straw, the liquid doesn’t just move up the straw because you’re sucking on it. The liquid moves up because the air is applying pressure to the top of the liquid which is relieved when you start sucking. That’s why the liquid is moving in the first place.”
Naomi Brandgan ’23 finished up their presentation by explaining why the can collapsed, “The vapor from the boiling water pushed the air out of the can. Cooling the can caused the water vapor inside to condense, creating a vacuum. The extremely low pressure of the vacuum inside the can made it possible for the pressure of the air outside the can to crush it.”
Since VoiceThread is an interactive platform, all students in the class can comment on presentations. Kendall Gordon ’23 commented, “I really like Evan’s video with his effects and different edits to make the video idea to make it more interesting.”
Naomi commented that she liked how he explained what he did incorrectly and how he fixed the variable that was wrong.
“We wanted our freshman chemistry students to continue learning through experimentation, even without access to our physical lab spaces,” said Alyssa. “This project structure of having students work in groups virtually allowed for student choice and curiosity. I was thoroughly impressed with the quality of the videos the students created as well as students’ perseverance in making procedural adjustments. Plus, these demonstrations were so exciting to watch.”
Watch this group’s full presentation and other group projects below.