Using a Computer Animation to Improve Students' Conceptual Understanding of a Can-Crushing Demonstration

Abstract

Students who received instruction including static chalkboard drawings and overhead transparencies to explain the behavior of gas particles in a can-crushing demonstration were given a demonstration-based quiz in which they were asked to predict what would happen when a similar can filled with water vapor was removed from the heat and sealed. They were also asked to explain their prediction in terms of the behavior of gas molecules. This paper reports some of the misconceptions that were identified from these students' explanations. As a result of these misconceptions, a computer animation depicting the chemical processes occurring in the can-crushing demonstration was created. Another set of students were instructed on the behavior of gas particles including the can-crushing demonstration and the computer animation and were given the same demonstration quiz. The responses from the two sets of students were then compared. The students who viewed the animation as part of their instruction on the particulate nature of gases were less likely to use explanations that relied solely on the application of mathematical relationships. These students were also more likely to report the importance of the condensation of water vapor and the pressure differential inside and outside the can in the can-crushing process.