Teachers college students' conceptions about evaporation, condensation, and boiling
✍ Scribed by Jin-Yi Chang
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 98 KB
- Volume
- 83
- Category
- Article
- ISSN
- 0097-0352
No coin nor oath required. For personal study only.
✦ Synopsis
This study administered an open-ended, written test to 364 students in a teachers college who were divided into four groups, according to their scientific learning background. After evaluation, some representative students were interviewed in a semistructured manner to obtain their conceptions. The test results showed that, although the science major students performed better than the nonscience majors, their understanding of the condensation and boiling concepts still needed to be enhanced. Most of the students did not hold the concept of saturated vapor, even in the science major (group A) students; that is, only 28.8% held this idea, and the percentages in the remaining groups (groups B-D) were less than 10%. The performances in each group on the tasks regarding the concept of boiling were not impressive; the answers from group A students about the bubbles within boiling water centered on air and water vapor, and the corresponding percentage was close; however, for the other groups, the percentage differences became larger and most believed what was inside the bubbles was air. Quite a few students knew the white "smoke" rising from the water kettle was tiny water droplets, and the highest percentage was only around 20%. It was also found that most students had only an ambiguous comprehension of the existence of water vapor in air, especially groups B and C, who were nonscience major students. In the interviews, some students still thought water evaporated once combined or contacted with air, and the idea of "condensation when cooled" was deeply rooted in the students' minds; although students knew that "water vapor is invisible," most still believed the white smoke was water vapor. Examining the students' ideas carefully, the researchers found out that learning difficulties regarding the aforementioned concepts could be a result of poor understanding of what water vapor is.