This study investigated the use of VCL to enhance student learning outcome in general chemistry and to assess the effect of different deployment strategies.
Introduction
Laboratory has been given a central and distinctive role in science education, and it is a common belief that there are rich benefits in learning from using laboratory activities [17]. The use of laboratory as a method of teaching develops students' reasoning, critical thinking, scientific perspective and problem-solving abilities [18]. Research has shown that hands-on experiences in the science laboratory play a central role in scientific education ([19] - [25]). This is largely due to both their presumed strong impact on student learning outcomes and performance and on their presumed practicality of professional preparation ([26] - [31]). Traditionally, STEM instruction at the undergraduate level has consisted of a lecture component and a hands-on laboratory component to reinforce classroom-based lecture concepts. Until recent years, physical, hands-on laboratory experiences were the only experiences available to fulfill these requirements. However, there are circumstances when offering hands-on experiential work to students is not practical. For example, distance education limitations, costly equipment or supplies, inadequate lab space ([32] - [34]), or time constraints [35] can be inhibitory barriers to the integration of effective hands-on experiences in the course curriculum. The use of virtual laboratories that rely on interactive simulations to convey learning objectives from the traditional lab experience has been shown to be effective. Because of the new development in computer technology and bandwidth maturity of recent years, coupled with the institutional challenges to provide adequate support for laboratory experimentation, scarcity of resources, security concerns and expensive equipment leading to the reduction of lab hours, there is renewed interests in considering alternative options. Accordingly, much research has been conducted regarding the advantages and disadvantages of computer technology on laboratory teaching and learning (e.g. [36]). In this regard, computer-based and remote data acquisition, virtual laboratory environments, and automated processes have all challenged and altered the methods and practices of what have traditionally been considered "hands-on" labs ([12]; [28]; [37] - [43]). These lab instructional modes have been discussed, from differing perspectives, in terms of their feasibility as stand-alone alternatives or best integration modalities to augment traditional laboratory. To date, there has been no consensus regarding the effectiveness of these alternatives and the effects these technological advancements might have on student laboratory learning. This study investigated the use of VCL to enhance student learning outcome in general chemistry and to assess the effect of different deployment strategies including usage as (1) as supplement to actual laboratory assignments; (2) pre-lab or post-lab activities; (3) homework or quizzes; (4) make-up labs; (5) classroom demonstrations; (6) inquiry-based learning activities in groups or their use as blended model alternating traditional to virtual laboratory. This paper discussed preliminary results obtained in the strategic use of VCL as a pre-laboratory assignment to a kinetic experiment in general chemistry.
Methodology
This study used a quantitative research design involving an intact class of second semester general chemistry students. The sample consisted of 13 undergraduate science majors. The setting was a historically Black College and University (HBCU) situated in the Southern part of the United States. The conceptual understanding construct was measured using a Chemistry Assessment Test in Kinetics (CATK) developed and validated by the researchers. The CATK was used to collect pre/post content knowledge before and after the VCL pre-laboratory assignment.
Data Analysis and findings
Data analysis was conducted using item analysis of pre/post data. Descriptive statistics were primarily used students to analyze and represent the findings and determine trends and learning outcomes relative to specific kinetic concepts. We observed a CATK score improvement of 13%. The results of the pilot study suggested that the use of VCL as pre-laboratory had a positive effect on students' conceptual understanding of reaction kinetics. The authors suggested follow-up studies to involve more students and investigating other general chemistry concepts.