Michael Clay, Ph.D., Department of Chemistry, The College of San Mateo;  May, 2007

> Introduction
> Laboratory Group Work
> Automated Data Collection Via MeasureNet
> Spreadsheet and Computer Analysis
> Modern Green Chemistry
> Summary

Introduction
The College of San Mateo (CSM) chemistry department has recently undergone major changes and innovations. The most externally obvious change has been the move into a new science building. All of the four chemistry laboratories are new and the three new general chemistry lab rooms are designed as dual function lecture and laboratory rooms. Every room is a smart room with full AV support. Additionally, the department has been fortunate to be able to purchase two MeasureNet laboratory data systems and enough computers to support two full labs. These changes have been the nucleus around which a redesign and upgrade of the chemistry laboratory program have been undertaken. These upgrades to the chemistry laboratory curriculum have been in four major areas: 1) lab classes now work as student groups rather than singles or partners, 2) labs use automated and computerized data collection and distribution, 3) computers are used for data analysis and lab exercises during lab periods and 4) chemical usage patterns have been modernized.

Laboratory Group Work
The new laboratory approach using group work has been facilitated by both the lab layout and the acquisition of the new MeasureNet data stations. Lab rooms were designed using 5 large tables with three students on each side of a table. This layout almost dictates that students work in groups of three during most laboratory exercises. This group work is further facilitated by the use of the MeasureNet data stations, where one station is used by each group of three students. Although it is still early in the changeover to group work in the laboratory, several trends are becoming obvious. Among these are: 1) working in groups facilitates other group activities and often leads to the formation of study groups outside of class periods, 2) group work helps lower the chemical usage of chemical labs, 3) group reports help lower the grading burden for the course and 4) working in groups is not always easy and is a skill that often needs practice. Trend 2 and 3 above are fairly obvious based on the lowering of separate chemical experiments and group reports lower the report count from 30 to 10. The other two trends deserve some further exploration.

Once students begin working in groups, there is often more communication between the members of the group both in and outside of class periods. When dry labs that involve studying and using chemical skills are done, the lab can become a caldron of student groups discussing the various points of the lab work and the instructor can then circulate among these groups as a facilitator of ideas. At CSM, work on these chemical skills is facilitated by the use of a laptop computer for each group. Students run computer programs that present and evaluate problems covering various skills and each group is responsible for turning in a set of completed skills at the end of the lab period. Although we use a large set of custom programs that were created at CSM, work could conceivably be Web based programs that can be supplied by various publishers. The current lab mix at CSM is such that about 2/3 of the labs during a semester can be completed and evaluated by each group before they leave the lab for the day. The other 1/3 of the labs, use larger data sets and are turned in as formal reports that use spreadsheet data analysis.  This mix of work facilitates group work during the lab periods where computer based learning is used and requires a manageable number of formal lab reports to learn data analysis and reporting.

As to the last of the trends mentioned above, the fact that group work is a skill that needs practice becomes obvious rather quickly. When students work as partners the dynamics are fairly easy to manage; however, once three people work together, group dynamics come into play. Among the early discovered facts are it is best not to assign friends to a group. Too often their work degenerates into play or two friends in a group gang up on the other group member. Another problem that comes into play is that sometimes one or more of the group members refuses to contribute to the work required of the group. The dynamics of getting a group to work well together can be a trying experience for members of the group, but it is becoming obvious that employers always seek employees who can work effectively in groups because this not only a necessary skill but also, one that takes some practice to develop. Thus, the move to doing group chemistry labs is a worthwhile venture.

Automated Data Collection Via MeasureNet
The changeover in the labs at CSM to automation and larger data set analysis has been facilitated by the purchase of MeasureNet data stations. While it is obvious that these are automated probe controllers, because of their networked capabilities with manual entry mode, each MeasureNet station is a central data node around which spreadsheet labs are facilitated. In essence, these stations become the laboratory data notebooks. All relevant data, whether collected by automated probes or simply measured and recorded by hand can be entered into data sets which result in a final spreadsheet for the entire lab. This aggregate data set can then be analyzed as a whole. Students can use the spreadsheet data, which is made available on the Web, to analyze not only their personal data, but also, data sets from various groups. To facilitate this work, some labs involve several groups working on the same unknowns and analyzing this collected data. Other labs such as calibrating calorimeter cups involve processing the data of the entire lab. Either way, the advantage of having complete lab data sets available at the completion of lab work is a revolution in the facilitation of spreadsheet data analysis of chemical labs. This factor makes the MeasureNet data stations an extremely valuable tool for implementation of modern chemical teaching labs.

Another factor that makes the MeasureNet automation of labs so useful is the real time network capabilities of the system. The master controller station, where the instructor works, becomes the central data station during the lab. This is much like the model of the language labs where a master station can oversee the work of each student station as language labs are practiced. In chemistry labs this means that during titrations or various temperature experiments, the instructor is able to look at the quality of the data as it is being collected. This allows problems in experiments to be diagnosed so that students can correct their work as they go rather than realize once they get home that they made data errors. For example, during titrations, the titration curves can be checked by the instructor and beyond the obvious check for the equivalence point being reasonable, other errors can often be diagnosed. When the drop counters are used they will report drops rather than mL volumes if errors in data collections occur. When student titration data shows drops rather than mL volume readings, the instructor can check to see that the students are reading volumes correctly. One common error is to misread the volume direction on the burette. This can be diagnosed by the MeasureNet showing drop instead of volume readings on its graphs. One common lab procedure that students now adopt is to check their saved data on the central data server before completing the lab work so they are sure their data has been recorded properly and that their data is reasonable. During collection such as heating-cooling curves this procedure allows students to realize that a bad data set has been collected so they can repeat the data collection before leaving for the day.

Spreadsheet and Computer Data Analysis
Since the MeasureNet stations result in all data being collected into a single spreadsheet file which is posted on a Web site, spreadsheet analysis of laboratory data is greatly facilitated. Although it would be possible in many instances for students to type their own data into a spreadsheet for final analysis, it would be difficult for entry of all of the class data into a single spreadsheet by hand. Even a traditional lab such as the Avogadro’s number by monomolecular films can benefit by such an approach. During this lab each table in the lab does a determination and enters their data into the MeasureNet station using manual entry. After the completion of the runs all of the data is put on the Web site and each group of students then analyze the average data for the entire lab class using a spreadsheet on laptop computers. The determination of a cup calorimeter constant is also carried out in this manner only with automated collection of the heating curves. Once all of the stations log their data, the data sets for all 10 stations in the lab are made available on the Web and using spreadsheets the data for the entire class is analyzed. The completed spreadsheet analysis is turned in before leaving the lab for the day.

Another lab exercise that greatly benefits from using the networked data stations and spreadsheet analysis is a volumetric glassware lab (see Appendix 1). In this lab, each student in a group measures 25 mL of water twice using a buret, a delivery pipet, a graduated pipet and finally a graduated cylinder. The 25 mL of water is then weighed and the density of the water at a measured temperature is determined. Each of the data points is entered into the MeasureNet station using manual entry. The final class data set includes 60 determinations for each piece of volumetric glassware. Using the power of a spreadsheet students are easily able to analyze these larger data sets and by finding averages and data set standard deviations, they are able to find the experimental density of water within a fraction of a percent error and at the same time they are able to analyze the precision and accuracy of each piece of laboratory glassware. Finally, students are introduced to modern laboratory data analysis techniques rather than being limited to small data sets.

Modern Green Chemistry
The move to group work and the MeasaureNet data stations has additionally facilitated the move toward increasingly green chemistry labs at CSM. Although the move is still not complete there has been much progress toward the removal of toxic chemicals and the reduction of chemicals that are used. The first stimulus was the general removal of hoods other than one distribution hood from two of the lab rooms. The single hood is sometimes used if ammonia must be used for a lab but otherwise chemicals and experiments which require hoods have been removed from the experiment list. Experiments such as dissolving copper in nitric acid and the Dumas lab were removed from the lab set completely. Concentrated acids and bases were removed from the chemical lists. Other toxic chemical experiments were removed or rewritten to remove the offending chemicals from the work areas.

The acquisition of the MeasureNet data stations helped the move to less toxic labs in two ways. First, by serving as the nucleus around which groups work, there was a reduction in chemicals used since individuals were no longer using the same amounts of chemicals. Even where partners were involved in the past, the move to groups of three experimenters represents a 30% reduction in chemical use.

The second way in which the MeasureNet stations helped to clean the labs is by allowing smaller amounts of chemicals to be used. Due to the improved titrations and thermoprobe data values chemicals could be reduced. The Hess Law experiment volumes were reduced from 100 mL total volume to 40 mL total volume which represents a 60% reduction in this experiment. Overall the reduction in chemicals used by the program has been significant and amounts to a reduction of 50% or more, while still maintaining a fairly tradition set of chemical lab exercises. In some cases, such as using the MeasureNet gas probes lab exercises such as Boyle’s Law can now be completed without resorting to the old methods of using Hg filled tubes.

Summary
The general chemistry laboratory program at CSM has been completely revamped to bring it into line with modern data collection and analysis techniques. Students now work in groups to collect and analyze their experimental data. MeasureNet data stations serve as the focal points around which groups are formed. These stations allow networked collection of computer spreadsheet formatted data which can be distributed via the chemistry Web site. Both automated and manually collected data are handled this way and student groups are expected to analyze their data by spreadsheet graphing and calculations.

This change in the traditional design of chemistry labs at CSM has resulted in increased student group work, improved spreadsheet skills among students, an increase in student scientific report writing skills, a decrease in the volumes of chemicals used during lab procedures and an increased exposure to modern data collection and analysis workflow procedures.

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