OBJECTIVE: Briefly state the objective(s) of your project. Remember, you have ~8 three-hour lab periods to accomplish this project — which isn’t a lot of time!!! Meet with Dr. Mirza to narrow the scope of your project.

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“TOPS” Format

You should write this document with your peers as the audience, so that a fellow 584 student can

easily follow your logic.

TITLE: The title should be brief yet specific about your intended project.

OBJECTIVE: Briefly state the objective(s) of your project. Remember, you have ~8 three-hour lab periods to accomplish this project — which isn’t a lot of

time!!! Meet with Dr. Mirza to narrow the scope of your project.

PLAN: This is the key section — it describes the technical approach that you will use to realize your objective(s). Maximum one page of text. This section

is where you show how you will use the scientific method to guide your

experiments.

SCHEDULE: Include at least six items that will mark your progress (aka “milestones”). Include dates for completing each milestone.

Overall maximum TOPS paper : two typewritten (12 point, 1.5 line spacing) pages!

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General Format (this is not a complete TOPS paper!)

Alfred E. Newman Chem 584 TOPS

March 2, 2005

TITLE Comparison of Trace Lead Ion Concentrations in Local Waters by AAS and PSA.

OBJECTIVE The objective of this research is to compare the concentrations of lead ion obtained from sources, including tap waters and surface waters, in the

Milwaukee area. Potentiometric stripping analysis (PSA) and atomic

absorption spectroscopy (AAS) will be the primary analytic techniques

used to measure the lead ion concentrations. Samples will be analyzed in

accordance with accepted protocols.

PLAN Separate paragraphs are written to: • Describe why lead ion concentration is important and thus worth

measuring at low levels;

• Describe how PSA and AAS are complementary measurements;

• Describe in detail how you will: optimize both methods,

collect/prepare samples, gather data, and compare results;

• Describe how you will address concerns such as: sampling

locations, sampling containers, shelf-life, sample preparation,

interferences, etc.

SCHEDULE The following milestones are scheduled: Task Milestone Completion Date

1.0 set-up PSA instrument March 28

2.0 optimize PSA response to Pb April 3

3.0 optimize AAS response to Pb April 8

4.0 analyze samples by PSA April 15

5.0 analyze samples by AAS April 24

For an example of a complete and well-written TOPS paper, see Appendix III.

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Appendix III. TOPS Example

Daniel R. Killelea CHM 524 TOPS Paper

October 8, 1998

Title Determination of Several Impurities in Whiskey. Objective Whiskeys come in a wide range of grades, and the higher the grade, the more

expensive it is. Low-cost whiskeys can be as little as $5 per liter, and high grades are commonly

about $50 to $60 per liter. The chemical differences between these grades must be rather

significant, or else why the great difference in price? What this project aims to achieve is the

measurement of the impurities in several commercially available whiskey brands. Additionally, an

effective method for extracting the organic compounds from an aqueous solution will be

developed.

Plan Whiskey is an aqueous solution, about 50%-60% (v/v), with ethanol as the major solute, between 35%-50% (v/v). To identify the impurities, the organic compounds must thus be

extracted from the liquor prior to quantitation. Simple liquid-liquid extraction (LLE) with a solvent

(e.g., methylene chloride) may be inefficient and generates hazardous waste.

Gas-Liquid Chromatography (GC) is effective at measuring trace quantities of thermally

stable, volatile organic compounds. Solid-Phase Microextraction (SPME) was developed for GC

to combine the sampling, matrix removal, enrichment, and injector introduction steps into a single

step. This solvent-free, simple, and inexpensive extraction technique has found numerous

applications in environmental analysis since its development earlier this decade. SPME can

obviate the need to use toxic solvents as is done conventionally.

The effectiveness of the SPME method will be determined, in comparison to a standard

liquid-liquid organic extraction using n-hexane. In SPME only a portion of analyte from the

sample is collected — the amount of analyte which is adsorbed onto the fiber coating may be

influenced by the matrix. In order to determine the effectiveness of each extraction method, both

will be used and then compared. Duplicate measurements will be made for statistical validity.

The series of experiment will be: (1) a sample of Whiskey will be extracted with solvent, and then

a chromatogram will be obtained; (2) the SPME experiment will be run on a sample of Whiskey,

and a chromatogram will be obtained; (3) the chromatograms of each method will be compared.

It is important to note that the quantitative results from the non-equilibrium SPME experiment

cannot be compared directly to the results obtained from the more exhaustive, solvent extraction

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— which is ideally made at solution equilibrium. Rather, qualitative comparisons (numbers and

resolutions of peaks) of chromatograms will be made.

The GC with flame ionization detector will not directly identify what impurities are present.

“Fortification” or “spiking” is the introduction of a known chemical at an exact concentration to the

sample. Spiking will be used with known standards to qualitatively and quantitatively identify

unknown peaks in the chromatogram (impurities). This should be useful for methanol and amyl

alcohols that are found in whiskeys. A comparison of the relative amount of impurities on

different brands of whiskey will be a significant determination. A few different brands, spanning

the range of prices, will be compared and the nature of the impurities determined.

Another impurity in whiskey is iron, according to the Jack Daniel’s internet site’s “distillery

tour”. GC will not be effective for the determination of the presence of iron; flame atomic

absorption spectroscopy (FAAS) will be used to determine the presence of iron.

Schedule

Milestone Completion Date

A. Optimize the SPME method based on the literature report Oct 28

B. Analyze test sample using direct injection and SPME Nov 3

C. Compare the results of SPME vs. LLE Nov 10

D. Analyze three commercial brands in duplicate Nov 19

E. Qualitative determination of iron by AAS (to be performed whenever the instrument is

available, independent of above milestones)