Chemical Education Today edited by
Michelle Bushey
Personal Multifunctional Chemical Analysis Systems for Undergraduate Chemistry Laboratory Curricula
Department of Chemistry Trinity University San Antonio, TX 78212
by Michael W. Vannatta C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506 by Michelle Richards-Babb* C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506 *
[email protected] by Sally D. Solomon Department of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104
In the United States, total enrollment in postsecondary institutions rose by 4.2 million students during the period 1993-2006 and is projected to rise by another 1.4 million by 2017 (1). Additionally, science and engineering bachelor's degrees have consistently accounted for roughly one-third of all bachelor's degrees awarded in the past 15 years (1). What this means for chemical educators is increased enrollments in chemistry courses, particularly general chemistry. This increased undergraduate enrollment can be corroborated by the steady rise in graduate enrollment in science and engineering fields since 1999 (1). The growing numbers of students enrolling in science courses at institutions of higher education are increasing faculty teaching loads. It is therefore important for educators to have the latest equipment to meet the growing demand for quality chemistry education. The laboratory is an essential component of undergraduate chemistry education. The American Chemical Society recommends that students working toward their bachelor's degree receive at least 500 total hours of laboratory instruction (2). As the number of students continues to rise, it is important to maintain individualized instruction within the teaching laboratory. This is especially important in light of recent reports detailing the difficulties in retaining students within hard-science fields such as chemistry (3-5). Fortunately, technologies such as personal multifunctional chemical analysis systems have helped educators engage students individually within large laboratory sections.
experiments. MCA systems typically offer sensors and probes appropriate for fields other than chemistry, including biology, environmental science, engineering, mathematics, physics, and physiology. The range of available sensors and probes is particularly useful given the proliferation of interdisciplinary undergraduate degree programs (6). Nevertheless, in this column, we will focus on how these systems can both enhance the traditional chemistry laboratory and enable outside lab work, all the while being economically viable even for departments with small budgets. Comparing Pasco and Vernier's MCA Systems and Customer Support There are two major manufacturers of MCA systems: Pasco (7) and Vernier (8). Pasco's premier system is called the SPARK Science Learning System, and Vernier's system is named LabQuest (Figure 1). Both the SPARK and the LabQuest systems can function independently of a computer tower or laptop. In addition, Pasco offers the slightly less expensive Xplorer GLX system, which is also a stand-alone instrument. Vernier offers a significantly less expensive instrument, the LabPro System, but to function, it must be interfaced with a
What Are Multifunctional Chemical Analysis Systems? Multifunctional chemical analysis (MCA) systems are stand-alone miniature science instruments. Depending on the needs of a specific course, the instruments can be used either in a traditional lab setting or out in the field. The systems are portable, can run on batteries, and let students collect, analyze, interpret, and transfer experimental data. These systems accommodate various scientific probes (including pH, conductivity, and voltage meters), thereby making possible many potential 770
Journal of Chemical Education
_
_
Figure 1. Photographs of Pasco's SPARK Science Learning System (left), and Vernier's LabQuest System (right). Photographs courtesy of Pasco Scientific and Vernier Software and Technology, respectively.
_
Vol. 87 No. 8 August 2010 pubs.acs.org/jchemeduc r 2010 American Chemical Society and Division of Chemical Education, Inc. 10.1021/ed100502s Published on Web 06/21/2010
Chemical Education Today Table 1. Comparison of Some Technical Specifications of the SPARK and Labquest Units Selected Specificationsa Instrument System
Screen Size
Onboard Memory
Sampling Rate, Hz
Weight, Grams
Data Connections
100,000
350
1 USB and 1 USB mini port
6 sensor channels
329
50,000
373
8 TTL input/ output lines
6 sensor channels
220
1 USB and 1 USB mini port
4 sensor channels; 1 channel for temperature; 1 channel for voltage
349
1 USB port
1 sensor channel
169
Vernier's LabQuest System
320 240 pixels; color
40 MB
Vernier's LabPro System
No screen (needs a computer)
12,000 data points
Pasco's SPARK Science Learning System
640 480 pixels; color
1 GB
1000
595
Pasco's Xplorer GLX System
1.30 0.300 ; black and white
0.1 MB
1000
∼300
a
Sensor Connections
Educational Price, USD
Less expensive units are also shown, but a detailed account of such units is beyond the scope of this article.
computer. A comprehensive comparison of these units, including their costs, is provided in Table 1. The less expensive instruments, while useful for laboratory curricula that can be adequately funded by low budgets, will not be discussed further. There are many similarities between the Pasco and Vernier premier systems. Both systems can operate on ac adapters or batteries. We tended to avoid battery use, however, because each unit comes equipped with its own ac adapter. Nevertheless, both Pasco and Vernier offer recharging stations with a small footprint that will simultaneously charge multiple units in a compact enclosure. Both companies also offer periodic software updates that are typically downloaded and installed on each unit via a USB flash drive. Both companies offer ample support via their Web sites. For instance, Pasco provides online training, downloadable videos, and a suite of quick-start and comprehensive manuals. Pasco also recently released the SPARK Science Learning System Emulator, which is a 1:1 recreation of the SPARK's screen with all of SPARK's functionality. The Emulator lets the instructor project the image of a SPARK screen on an overhead projector for an entire classroom to see. Lastly, Pasco allows and encourages educators to design their own custom SPARK labs. The company provides detailed literature that instructs a user on how to customize the SPARK for use with a particular experiment. Vernier's support is nearly identical to Pasco's, right down to the Emulator capability. The only appreciable difference is that, whereas Pasco offers online training only, Vernier offers handson training at different cities throughout the country and at various educational conferences. Features of the SPARK and LabQuest Systems SPARK Science Learning System The SPARK Science Learning System has a large color display that provides finger-touch navigation. The unit comes equipped with temperature and voltage sensors. It can also accommodate two additional sensors, including chemistry-specific sensors that provide measurements for pH, drop counters, redox, conductivity, and colorimetry. Data can be displayed in many ways during the course of an experiment. Graphical, digital, running tables, and analog display options are available to the students. Once data have been acquired, several functionalities let the user investigate further. For instance, students can perform graphical and statistical analysis on their data and then
r 2010 American Chemical Society and Division of Chemical Education, Inc.
_
export it via the USB port for use in advanced software environments. The SPARK has 60 preinstalled experiments, including 10 chemistry-specific labs. These preinstalled experiments let users implement the device within their specific curricula immediately. Roughly 100 other sensors are available for purchase and are applicable to fields such as biology, environmental science, engineering, mathematics, physics, and physiology. The average cost of an additional sensor is around $100. Lastly, the SPARK unit is designed to take a fall from a lab bench without suffering any damage. (That said, we would not recommend testing that claim!) Vernier LabQuest System The Vernier LabQuest System's screen display is in bright color with easy-to-understand icons that clearly lead the user from the home screen to a data table, a plot, a keyboard, or a screen with lab instructions. The LabQuest unit comes equipped with a temperature sensor and a microphone. The stylus, which is unique to the LabQuest system, is comfortable to use, requiring minimal pressure to select a function. Hardware keys found on the LabQuest face can substitute for the stylus for most major functions, including moving among any of the screens described above. Even first-time users should have little trouble collecting data. LabQuest automatically recognizes the probe in use. Changing units or choosing a mode of data entry is readily accomplished from the home screen. Regardless of whether the new user chooses to get started by exploring icons, buttons, and menus or by referring to online support, we have found that common problems are fairly easy to overcome. For example, suppose that nothing happens when a user taps an object on the screen. Pressing the Home hardware key and then selecting Control Panel followed by Calibrating Screen corrects the problem with simple instructions. Like the Pasco unit, Vernier's device offers preinstalled laboratory experiments. The LabQuest comes embedded with more than 100 laboratories and 200 experiments, all of which are sequestered into subject areas and available for purchase. More than 100 additional sensors are compatible with the LabQuest unit, also averaging about $100 in cost. Conclusions The incorporation of MCA systems into undergraduate chemistry laboratories puts modern chemistry tools into the hands of undergraduate students. Each student or group of
pubs.acs.org/jchemeduc
_
Vol. 87 No. 8 August 2010
_
Journal of Chemical Education
771
Chemical Education Today
students now has access to instrumentation that was often shared or absent in the not-so-distant past, a change that saves large amounts of “waiting around” time. Furthermore, some undergraduate students were not exposed to a wide variety of chemical instrumentation until upper-level courses. Exposing first-year students to as many chemical analysis tools as possible will only assist in attracting and retaining them within the chemistry discipline. Finally, the portability of MCA systems allows for the possibility of field and interdisciplinary experiments, which will further raise student interest in the material. In addition to being used in undergraduate laboratories, outreach programs that deliver equipment to secondary schools have used MCA systems (9). Transporting hand-held MCA systems and their probes is much more convenient than supplying cumbersome laptops and interfacing panels along with the probes. Teachers who have previously used the laptops and interfacing panels report that they prefer the new SPARK and LabQuest devices. According to those teachers, the experimental setups are easy to understand and implement. Our experience has demonstrated that students have little trouble following instructions and obtaining data. We have enjoyed success when integrating these devices into our chemistry department curricula and have received positive feedback from both faculty and students. At West Virginia University, many students have enjoyed having their own SPARK system and not waiting for other students who might not be moving at the same pace. Instructors at Drexel University have commented on how experimental setups are quicker, easier to understand, and much more convenient when using the LabQuest units. Both the SPARK and the LabQuest devices would make excellent investments for improving one's chemistry department. Choosing which system to purchase might be difficult, however, because the two units are so similar, so we suggest that the reader research which system would best fit
772
Journal of Chemical Education
_
Vol. 87 No. 8 August 2010
_
within one's university or college. Consider these factors when choosing which device is best: student body needs, institution budget, type of curriculum, variety of lab experiments, and total number of devices needed. Both companies will usually provide demonstration units and some time to experiment with each system. Acknowledgment The purchase of the equipment was supported by the C. Eugene Bennett Department of Chemistry and the Eberly College of Arts and Sciences. M.W.V. and M.R-B. thank all the general chemistry instructors for their feedback and patience as these units were integrated into the curriculum. S.D.S. wishes to thank the state-funded Drexel Science in Motion outreach program, online at http://www.philasim.org/ (accessed Jun 2010), which delivers equipment, including LabQuest, to Philadelphia schools. Literature Cited 1. National Science Board. Science and Engineering Indicators (NSB 10-01); National Science Foundation: Arlington, VA, 2010. 2. Crim, F. F.; Polik, W. F. J. Chem. Educ. 2004, 81, 1695–1696. 3. Wood, W. B.; Gentile, J. M. Science 2003, 302, 1510. 4. Alberts, B. Cell 2005, 123, 739. 5. Summers, M. F.; Hrabowski, F. A. Science 2006, 311, 1870. 6. Boix Mansilla, V.; Dawes Duraisingh, E.; Miller, M. L.; McAlpine, S.; Rhodes, A. Integrating Disciplines To Deepen Understanding: A Framework for Design; Harvard University: Cambridge, MA, 2006. 7. Pasco Probeware Getting Started Web Site. http://www.pasco.com/ products/probeware/Index.cfm (accessed Jun 2010). 8. Vernier Products LabQuest Web Site. http://www.vernier.com/ labquest/ (accessed Jun 2010). 9. Science in Motion Welcome Page. http://www.philasim.org/ (accessed Jun 2010).
pubs.acs.org/jchemeduc
_
r 2010 American Chemical Society and Division of Chemical Education, Inc.
