Qualitative Data
A close reading of the student responses to the questions in the laboratory write-up led to several observations. First of all, 20 of the 25 students showed direct evidence of linking the microscopic to the macroscopic levels of understanding. Secondly, several misconceptions concerning the behavior of gases at the microscopic level were exposed. Thirteen of the twenty-five expressed a belief that as the volume of a gas decreased that the particles increased in speed and that explained the increase in pressure. Modifications in the lab write-up will be tested this summer to address that misconception. Two other minor misconceptions were also revealed: collisions between molecules contribute to pressure, and a collision with container walls causes particles to slow down. Once aware of these or other misconceptions the instructor can design activities that will help address these misconceptions (e.g. the instructor can ask students to use the software to "prove or disprove the following assertion: particles slow down when they collide with the container walls."). This approach is possible because of the flexible nature of the software and is consistent with the research on conceptual change.