CHEM 311- Laboratory

FRIDAY 2:30 - 5:30 (B210-460)

LIST OF EXPERIMENTS

 One Week Labs (Wet Chemical Techniques)                                                                     

1.     Lab Orientation (Sept 07, 2018)

        Lab Manual Introduction

        Lab Manual Appendices

Introductory Exercise

Standardization of NaOH - worked solutions

                    Summary of class data for [NaOH] standardization 2012

     2.     Electrochemical Metering Devices and Field Portable Instruments (Sept 14, 2018)                     (Data Tables/5 - due date Sept 20)

                    Example Data Table (Sp. Conductivity)

Student Feedback on Data Tables

3.          Sample Collection and Analysis Field Trip (Sept 21, 2018)                            (Principles, Rationale and Results/10 - due date Sept 27)

 Student Feedback on Principle of Method

4.          Alkalinity of Groundwater (Sept 28, 2018)                                                      (Data and Results Tables/10 - due date Oct 4)

Student Feedback on Data and Results Tables

5.          Dissolved Oxygen in Surface Waters (October 5, 2018)                                    (Full Report/20 - due date Oct 16)

6.          Nitrates in Drinking Waters (October 12, 2018)                                                   (Technical Report/15 - due date Oct 23)

        Excel Spreadsheet for Cal Curves and Error Analysis of Least Squares

8.          Ortho-Phosphate Analysis in Wastewater (October 19, 2018)                              (Full Report/20)

9.          Fluoride Ion in Groundwater and Toothpaste                         (Technical Report/15)

 Two Week Labs (Sample Prep and Instrumental Analysis)

        Metals in Sediment Sample by AAS                                         (Report/20)

         Organic Contaminants                                                                (Report/20)

 

LATE PENALTIES FOR LAB REPORTS

10% per week penalty up to two weeks, after which lab reports will not be accepted.

Students must pass both the lab and lecture portions in order to receive a passing grade in the course.

 

Formal Lab Reports

CHEM 311 Lab Reports are submitted as stand alone formal reports (unless otherwise noted) that are to be written in a impersonal voice in typed format. Your lab report should present the principles of the chemistry and/or instrumentation employed, calibration techniques, data handling, an estimate of experimental uncertainity and a general awareness of the context and significance of the results. 

TITLE PAGE AND IDENTIFICATION: Course number. Name of student. Name of partner. Date. Unknown #.  The title should provide the reader with both the analyte and the matrix studied and give some indication of the technique employed.  E.g., The Analysis of Fluoride Ion in Toothpaste Using An Ion Selective Electrode.

PRINCIPLE OF METHOD:  Describe the principles involved in relating the measured quantity (e.g., volume of titrant, absorbance, potential etc.) to the analyte concentration.  For wet chemical techniques, include the stiochiometry of chemical reactions that will be used in the calculation of results.  For instrumental techniques, describe the principle of operation of the instrument itself.  Diagrams may be useful here for instrumental methods.  Do not describe details of the procedure.

PROCEDURE:  Not necessary except to specify modifications to the lab manual.

DATA:  Tabulate data with descriptive headings and footnotes providing details.  Data tables should be able to stand alone providing enough information that the reader could carry out necessary calculations without having to go hunting for additional information. For example, in a data table summarizing titration volumes, be sure to include the titrant concentration and the sample volume. 

CALCULATIONS AND RESULTS:  Show a representative calculation used to convert measured quantities into reported results. Include calculations used to estimate uncertainities. Figures and graphs must be properly labeled. Use spreadsheets (such as Excel) to carry out repetitive calculations and generate calibration curves (include equation of best fit line and correlation coefficients). In most experiments you will be expected to estimate the experimental uncertainty either as a standard deviation or with a 95% confidence limit. 

DISCUSSION:  State your result/s and give some context for the magnitude (high, medium or low). For example, report the levels of Fluoride ion in commercial toothpaste, other foodstuffs or drinking water. Be sure to convert to common concentration units, if necessary. Comment on the precision (RSD) and/or accuracy (% bias) of the method using your data and the reported values given in Standard Methods. Discuss possible interferents and other sources of error. Conclusion paragraph should clearly report final results for all samples with 95% CL and n (# of replicates).

LITERATURE COMPARISON:  Briefly summarize one alternative method of analysis used to measure the same analyte. Explain how the analyte is quantified and summarize any advantages/disadvantages of the alternate method. You may use the primary literature such as Analytical Chemistry or secondary sources such as Standard Methods or an Analytical Chemistry textbook.     

REFERENCES:  All references cited in the report should be listed as numbered endnotes in the style adopted by Analytical Chemistry.

Typical Marking Scheme

See Additional Lab Resources (including Experiments, downloadable Excel spreadsheets, list of experimental references in the Journal of Chemical Education) via the textbook website