Chemistry and biochemistry are experimental sciences and experience working in lab is an essential part of most courses in our department. The particular focus of the Chem 260 lab is learning how to investigate the thermodynamic, equilibrium, and kinetic properties of reactions. During the semester you will learn how to make quantitative measurements with appropriate precision and accuracy, learn how to use several routine quantitative methods of analysis, learn how to design and carry out experiments, learn how to evaluate critically experimental data, learn how to report responsibly the results of an experiment, and learn how to work as part of a small research team.
The schedule below outlines the work we will complete during our lab sessions and due dates for written reports. All experiments and related materials are in your lab manual.
- January 28: introduction to lab and data analysis workshop (penny.xlsx, tables and figures with comments)
- Preliminary Experiments
- February 4: Preparing Solutions (electronic notebook due at end of lab)
- February 11: Newton's Law of Cooling (draft of results due February 17 and returned on February 18 in lab; final draft due on February 26)
- February 18: Determining the Amount of Acetic Acid in Vinegar (draft of procedure due on February 24 and returned on February 25 in lab; final draft due on March 4)
- February 25: Characterizing an Oscillating Reaction (draft of introduction due March 2 and returned on March 3 in lab; final draft due March 11)
- Open-Ended Project-Based Experiments
- March 3 and March 10: Thermodynamics of Hydrogen Peroxide's Decomposition (formal and short reports due March 20; oral report week of March 30)
- March 17 and March 31: Thermodynamics and Solubility of Calcium Hydroxide (formal and short reports due April 10; oral report week of April 13)
- April 7 and April 14: Acid Dissociation of Organic Dyes (formal and short reports due April 24; oral report week of April 27)
- April 21 and April 28: Kinetics of the Bleaching of Dyes (group poster due by May 8; template for poster)
- May 5: check-out of lab
- Laboratory Notebook. Experimentation is the framework on which we construct our understanding of chemistry and biochemistry. A proper framework, of course, has a foundation and this foundation is a lab notebook or a field notebook. Our collective confidence in chemistry and biochemistry depends on experimentation that is well documented; for this reason, you will maintain a permanent electronic record of your work in lab that is accessible at all times to each member of your group and to your instructor via a shared folder on a Google Drive. Suggestions on how to maintain this electronic notebook are available in the lab manual. Although your electronic notebook is evaluated only once during the semester, at the conclusion of the first preliminary experiment, I frequently consult it as I evaluate your written reports.
- Lab Reports. You will present the results of your work in lab through a series of reports. The reports for the second, third, and fourth preliminary experiments will focus on the main sections of a good written report: (i) thoroughly presenting results using a combination of words, figures, and tables, (ii) concisely outlining the experimental procedure to ensure reproducibility, and (iii) effectively placing your work in a broader context. You will prepare these reports as a group using a process that includes an initial draft and a final draft. For the first, second, and third project-based experiments, each group member will complete one formal lab report, one short report, and one oral report; as a group you will prepare a poster to present the results of the fourth project-based experiment. Specific details regarding these reports are included in the lab manual.
- Grading. The lab reports for the preliminary experiments are worth 25 points each. For the project-based experiments, the individual formal lab report is worth 100 points, the individual short report is worth 50 points, the individual oral report is worth 25 points, and the group poster is worth 50 points. An assessment of your contributions to group work by your peers accounts for 25 points. Participation is worth 25 points, with one point deducted each week if you are up to 10 minutes late, two points if you are up to 20 minutes late, and three point if you are more than 20 minutes late.
- Making Good Use of Time. You can complete all laboratory work in the time available if you come to lab prepared. At a minimum you should read the experiment before coming to lab and think through what you need to accomplish during the laboratory period. You also should familiarize yourself with the instrumentation and software by reading the relevant materials included on this web page. For project-based experiments, it is essential that you meet before you begin work to finalize your plans, and to meet between laboratory sessions to evaluate your data and to make plans for further work; this planning and discussion is critical to your success.
Safety in the Laboratory
Although a chemistry or biochemistry laboratory is equipped with chemicals and equipment that can result in injuries, there is no reason that a laboratory inherently is less safe than other environments where one is exposed to caustic and/or reactive materials, sharp objects, and hot items. You can work safely in a laboratory if you pay attention to how you dress for lab, how you prepare for lab, how you work while in the lab, and how you clean up at the end of lab. You will receive a copy of the department's policy regarding laboratory safety; an additional essay on working safely in lab is included in the lab manual.
Working as Part of a Team
Working with other students as part of a small research team is a rewarding experience. There is an abundance of evidence in the educational literature that the process of discussing an experiment with peers leads to a deeper understanding of the specific experiment and the broader science that underlies the experiment. In addition, working as part of a group is a valuable skill that is of increasing importance to employers, to graduate programs, and to health professionals. Indeed, you will spend most of your professional career working closely with others. An effective group, however, does not happen without some effort on your part. The lab manual includes some tips on working as a group that will help you get more out of this experience.
Analytical Measurements and Techniques
As you work in the laboratory, you will make a variety of different measurements. A procedure, for example, may instruct you to obtain a portion of a solid reagent, to dissolve that reagent in a suitable solvent, to bring the solute and solvent to a known volume, and to measure the solution's absorbance at a wavelength of 450 nm. Although these instructions seem straightforward, each step requires that you make a carefully considered decision about how accurately and how precisely you need to measure a mass or a volume, and requires an understanding of the instrumentation used to measure absorbance. Essays on these and other related topics are included in the lab manual.
Analyzing Data and Reporting Results
Although the work you do in lab is important, it is but one step in the larger process of working as a scientist. Equally important is the planning that goes into identifying a research project and designing suitable experiments, and, after completing your work in lab, the analysis of your data and its presentation to others. Essays on these and other related topics are included in the lab manual.
Working with Vernier's LabQuest 2 and LoggerPro 3
Gathered here are guides to working with Vernier's data collection interface (LabQuest 2) and to the software used to gather and display data (LoggerPro).