Students' learning in inquiry-based investigations has drawn considerable attention of the science education community. Inquiry activities can be viewed as knowledge construction processes in which students are expected to develop conceptual understanding and critical thinking abilities. Our study aimed to explore the effect of experiments with different levels of inquiry on students' interactions in the laboratory setting, as well as on students' written arguments and reflections. Our results are based on direct observations of group work in college general chemistry laboratories and analysis of associated written lab reports. The analysis of students' interactions in the laboratory was approached from three major analytic dimensions: Functional analysis, cognitive processing, and social processing. According to our results, higher levels of inquiry were associated with an increase in the relative frequency of episodes where students were engaged in proposing ideas versus asking and answering each others' questions. Higher levels of inquiry also favored episodes in which experimental work was approached in a more exploratory (versus procedural) manner. However, no major changes were observed in the extent to which students were engaged in either interpretive discussions of central scientific concepts and ideas. As part of our study we were also interested in characterizing the effects of experiments involving different levels of inquiry on the structure and adequacy of university general chemistry students' written arguments, as well as on the nature of their reflections about laboratory work. Our findings indicate that the level of inquiry of the observed experiments had no significant impact on the structure or adequacy of arguments generated by students. However, the level of inquiry of the experiments seemed to have a major impact on several areas of students' written reflections about laboratory work. In general, our results elicit trends and highlight issues that can help instructors and curriculum developers identify strategies to better support and scaffold productive engagement in the laboratory. Our results suggest that careful design and implementation of instructional interventions may be needed to maximize the learning effects of the more open-ended inquiry activities at the college level. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]