1343 PHYSICAL CHEMISTRY LABORATORY

SPRING TERM 2003 (03-2)

Contents

Course Structure
Evaluation
Schedule
Group Assignments
Group Compositions
Report Writing Guidelines
Report Grading Sheet
Notebook Grading

CREDIT HOURS: 2

CLASS MEETINGS: Tues. 1:00-4:50 PM. (118/102B/112 E & S)

INSTRUCTOR: Dr. Richard C. Ulsh

OFFICE: 112A (Analytical Lab) Engineering & Science

OFFICE PHONE: 269-2903

E-MAIL: ulsh@pitt.edu.

OFFICE HOURS: MWF 3-4 PM. Other times by appointment (see me after class); or just stop by my office to see if I am available.

TEXTS & ANCILLARY MATERIALS:

Experimental Physical Chemistry, A Laboratory Textbook, 2nd. edition, Arthur M. Halpern, Prentice Hall, 1997 (responsible for all reading assignments).

Quadr. ruled bound compositions notebook.

Macintosh or PC (preferred) 31/2 inch floppy disk to store data, and write lab reports.

ADDITIONAL SOURCES (2-hour library reserve, cross-referenced with CHEM 1342):

Writing the Laboratory Notebook, Kanare, H. M., American Chemical Society, 1985 (read chapters 1,2,5, and 6)

Braun, C. D.; Smirnov, S. N. J. Chem. Ed. 1993, 70, 612, "Why is Water Blue?".

Chemical Kinetics, 3rd. ed., K. Laidler, Harper & Row. (Advanced but very readable)

Molecular Orbital Theory for organic chemists, A. Streitwieser, John Wiley. (The whole story of Hückel MO theory at an organic chem. level)

Molecules and Radiation, 2nd. ed., J. I. Steinfeld, The MIT Press, Cambridge, Massachusetts. (Molecular spectroscopy, complete)
*Molecular Reactions & Photochemistry, Depuy & Chapman, Prentice-Hall.
*Molecular Photochemistry, N. J. Turro, W. A. Benjamin, Inc. (a classic and clearly written text)

Molecular Quantum Mechanics, 2nd. ed., P. W. Atkins, Oxford University Press. (Introductory graduate level, more extensive)

Mechanisms of Chemical Reactions, Gardiner, Benjamin Inc. (Lots of examples)

*Physical Chemistry, 2nd. ed., Barrow, McGraw-Hill. (Simplified approach)

*Physical Chemistry, 3rd. ed. G. Castellan, Addison-Wesley. (Different approach with more complete math. steps)

*Quantum Mechanics in Chemistry, M. Hanna, Benjamin-Cummings. (Good Hückel MO section)

Quantum Chemistry, 2nd. ed., J. P. Lowe, Academic Press. (Written with little jargon, in the way students communicate--personal copy)

*Symmetry and Spectroscopy--An Introduction to Vibrational and Electronic Spectroscopy, D. C. Harris and M. D. Bertolucci, Dover Books (Readable intro. to applications including HMO theory, only $13.95 in paper)

*Symmetry in Bonding and Spectra-An introduction, Bodie E. Douglas and Charles Hollingsworth, Academic Press.
*Symmetry Through the Eyes of a Chemist, I. Haigittai and M. Haigattai, Plenum Press (dare I say "light reading")
*Symmetry in Molecules, J. M. Hollas, Chapman and Hall Ltd. (Simplified group theory, very readable)

COURSE STRUCTURE: You will work in teams of two to complete the experiments. Each group will elect a principal investigator (PI) whose task it is to lead the team effort for an experiment. That role will rotate during the semester. Other formal roles include: instrument specialist, report writer, and report reviewer. We will be performing two different experiments simultaneously. Each experiment will be allotted two weeks for the lab work and group data analysis and interpretation. Approximately one week later the written report is due.

The laboratory is intended to introduce you to semi-independent work in physical chemistry. These experiments generally supplement the lecture rather than duplicate it. It is not always possible to cover the theory in lecture before applying it in the laboratory and in some cases particular aspects of the experiments are not covered in lecture at all. As a consequence, you will be expected to acquaint yourself with the principle involved in the experiment which is detailed in the Introduction to each experiment.

The teaching technique used is one of guided discovery, I often give clues and hints, as you discover the answer. You are expected to think and be creative in the use of equipment, and the search for answers, as befitting an upper-class laboratory. Your notebook will be graded based on evidence of this process. You should come to the lab with an understanding of the experiment and prepared to complete the experiment. During the first week of the experiment the instructor will answer questions pertaining to instrumentation. In subsequent weeks, team members who had hands-on experience with each instrument are expected to instruct other team members on use of the apparatus. Peer teaching is a valuable learning experience. If your team is unable to figure something out then bring it to the instructor.

After data collection, analyze the data invididually, and interpret the data collectively. Then choose one member, not the PI, to discuss the results with the instructor before writing the report.

This is an intensive writing course! Lab reports should be written with a word processor for easy editing. Divide up the work involved in writing the report, then assemble all tables, graphs, etc, into one report for your group. You will receive one grade for the report. The report reviewer should check the report for all the required areas on which it will be graded and make recommendations to the writer in time for changes to be made.

Since you will have about one week to complete the report from the day the experiment is completed, it would be a good idea to start writing the lab report as you do the experiment, i.e. start graphing data and preparing tables and doing calculations. Computer-lab problems are not an acceptable reason for lateness, since you have a week to complete the reports and you may hand write them, so don’t wait until the last minute. Be especially aware of heavy use times near exams and at the end of the semester.
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EVALUATION:

Reports (group score)	70%
Notebook (individual)	10
Participation (individual lab contribution)	10
Analyzed data (individual for each experiment) or quiz	10
Total	100%

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HONESTY: I start out trusting everyone, but for the record must state the following. Academic integrity is the expected norm; cheating and plagiarism will not be tolerated. Reports are to be individually written, must be properly referenced and any plagiarism, cheating or assisting others to cheat will result in a zero for the report. Plagiarism includes copying information from another person’s computer disc. You are encouraged to help each other with the experimental work and understanding of the results, however, reports are to be written individually!

SUPPORT SERVICES: Macintosh and PC computers, for graphical or statistical analysis, and report writing, are available in the computer labs in Blackington (Rm. 230 is always open) and in E & S 102. Questions on word processing or spread sheets may be answered by the Lab staff; StatView questions should be directed to the instructor only.

SAFETY: Follow all recommended safety practices described in each experiment. Goggles are mandatory when working with hazardous chemicals or glass vacuum lines. Refer to the Material Safety Data Sheets (MSDS) for each chemical substance used.

TENTATIVE LABORATORY SCHEDULE

EXPERIMENT	EXP. NO. (TEXT)	START TUES.	REPORT DUE	NOTES
0. Introduction to spreadsheets and error analysis.	Assignment #1	Jan. 7	Jan. 14 1 pm	Do word processing & spread-sheet problem individually.
A. The Entropy of Mixing	7	Jan. 14	group A:  group B:	Two groups alternate experiments A & B
B. Viscosity of Liquids. Part I: Low Viscosities	17	Jan. 14	group A:  group B:
C. Bomb Calorimetry: Heat of Formation of Naphthalene or Sucrose	5	Feb. 11 and 18	group A: group B:	Two groups simultaneously; 1st week get calorimeter constant; 2nd wk. do unknown
D. The Kinetics of a Homogeneous Reaction in Solution: Method 1	21	Feb. 25	Group A	Two groups alternate experiments D & E
E. The Kinetics of a Diffusion-Controlled Reaction: Modifications	22	Feb. 25	Group B
F. Excited State Properties of 2-naphthol  Part I: Acidity Constant Expt_34_Part_I.html	34	April 1	Group A: Mini-symposium 4/15	Group A only. Do first approach, absorption maxima of free acid and conjugate base, p. 528.
Excited State Properties of 2-naphthol Part II: Deprotonation/Proton-ation rate constants Expt_35_Part_II.html	35	April 1	Group B: Mini-symposium 4/15	Group B only. Procedure 1 and 3 on p. 541.
F. Rotational-Vibrational Spectrum of HCl: FTIR Operation	37			Two groups, separate gas cells
G. The Vibrational Spectrum of SO2 FTIR Operation	38			Two groups, separate gas cells
NS Undergraduate Research Symposium: Poster Grading criteria April 11, Wednesday afternoon (no 1342 class)				Each group will prepare a poster on one experiment (no report required); turn in poster slides

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GROUP ASSIGNMENTS

We will start by dividing the class into groups based on the principle of maximizing the diversity of skills, experience, courses taken and genders, etc.

Roles of group members:

Principal Investigator (PI)—organizes the group to accomplish the goals of the experiment. Assigns roles to group members, or gets volunteers to do such things as weigh out sample, read gauges, etc.

Instrument specialist (IS)—responsible for knowing how to operate the apparatus used in the current experiment and demonstrating its use to others in the group. The instructor will work with this person mainly, to train them in use of the apparatus. Questions about the apparatus should be discussed with this person first then brought to the instructor.

Report writer (RW)—organizes the group effort to bring together graphs, tables, references, essentially all parts of the report and is responsible for turning out the final report.

Report reviewer (RR)—this person ensures that the report addresses the points required in the experiment and satisfies the Report Writing Guidelines in the course syllabus.

Everyone in the group is required to participate in the experiment, analyze the data individually, and contribute parts to the report in addition to the above formal roles. Each group will decide date the report is due, based on their schedules. They will inform the instructor of that date after the experiment is finished. Roles will rotate so everyone gets to do as many roles as possible by the end of the term.
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GROUP COMPOSITIONS

Experiment A: Entropy (7)

Group A	Group B
Role              Name	Role          Name
PI Andrew	PI  Nick
IS & RR Kelly	IS  Jason
RW  Dan	RW      Nathan
---	RR Troy

Experiment B: Viscosity (17)

Group A	Group B
PI Dan	PI Jason
IS & RR Andrew	IS Nick
RW Kelly	RW Troy
---	RR Nathan

Experiment C:  Calorimetry (5)

Group A	Group B
Sucrose enthalpy of formation	Naphthalene enthalpy of formation
PI Kelly Dalton	PI Troy Cover
IS & RR Dan Meleason	IS Nathaniel Grove
RW Andy Shaffer	RW Jason Ackerman/ RR Nick Turcato

Experiment D: The Kinetics of a Homogeneous Reaction in Solution (21)

Group A	Group B
PI
IS
RW
RR

Experiment E: The Kinetics of a Diffusion-Controlled Reaction (22)

Group A	Group B
PI	PI
IS	IS
RW	RW
RR	RR

Experiment F:

Group A

Group B

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REPORT WRITING GUIDELINES

The goal of a scientific report is to make it easy for the informed reader to find what you have done, see final values and decide on their accuracy. Make it easy for the reader to find these and you will receive a good grade. Clearly present data graphically, including ‘bad’ data, not included in conclusions. All results must be presented in a table and included in the body of the report.

The grade will consist of two parts: one for the science and one for the writing. Be sure to keep a disc or photocopy of every lab report you turn in!

1. TITLE PAGE: The title of the report, author's name, partner's name, date performed and date submitted form the contents of the title page. Submit with all reports.

2. ABSTRACT: This should be a concise statement of the work done and experimental method used, including the major results obtained. Avoid a play-by-play review of the experiment. The abstract should usually be only one or two paragraphs and is written last, after the report is completed.

3. PURPOSE: Briefly state what the reason is for doing the experiment.

4. EXPERIMENTAL PROCEDURE: The equipment and techniques are conventional in most experiments, and only enough discussion to indicate that you know basically what you did. Indicate any procedures or equipment that differs from that in the lab text. No copies of apparatus are necessary.

5. DATA: Put data in a table whenever possible, including ‘bad’ data that you do not use to calculate results. You may combine it with results if it makes sense to do so.

6. CALCULATIONS AND RESULTS: Give a sample calculation for each type of result. Do this in a manner such that anyone with an understanding of the experiment can follow the discussion and calculations. Define all symbols. State what part of your data is used in each calculation. It is desirable that these results are in a form such that the reader can repeat the calculations and see general trends, i.e. use tables and graphs.

7. DISCUSSION OF ERRORS: This discussion should be as quantitative as possible. All errors should be propagated throughout the experiment (see chapter 1 of Experimental Physical Chemistry). Report errors as the mean value ±x, where x is the 90 or 95% confidence limit.

8. CONCLUSIONS: The results should be analyzed in terms of the ideas expressed in the theory section of the lab text for that experiment and a comparison with the literature or accepted values should be made. If your results are badly in error, suggest reasons for this. They should, as much as possible, be specific reasons, not simply "human error" or the like. Answer any questions here.

9. LIST OF REFERENCES: All numerical quantities except physical constants should be referenced. References can either be put at the bottom of the page or collected at the end of the report. It is rarely useful to paraphrase or quote a source, but if this is done a reference must be given. A fact that is available in only one or a few places in the original literature should also be referenced.

It is plagiarism to quote or closely paraphrase a book, etc., without acknowledgment. Your reports should be in your own words, and hopefully the information contained in them will be drawn from several sources. See HONESTY.

10. GRAMMAR AND STYLE: Scientific papers should be written in acceptable English. You may use either first person pronoun (I or we) or third person (it) as appropriate. Reports written on a computer will facilitate revision. Use a graphing application to graph data, determine slopes, intercepts, and errors in these quantities. Comments on style will be made, as well as grammar and spelling.

11. COLLABORATION: It is clearly in the student's advantage to discuss the material in a report with classmates, particularly with respect to understanding theory. It is very important, however, that students actually write their reports independently. This includes doing the literature research and calculations on your own. Independent calculations that lead to identical results to 3 or more significant figures do not occur frequently! See HONESTY.

12. NOTEBOOK: All data and observations are to be recorded in a bound notebook. (Refer to Writing the Laboratory Notebook, by Howard M. Kanare, American Chemical Society, 1985; and your lab text). Use an ink pen for all entries. Errors are to be corrected by drawing a single line through the error and writing the correct value above or beside the original. The instructor will evaluate your note keeping procedures during the semester.

13. A penalty of one letter grade will be assessed for each week or fraction thereof that a report is late.

14. Make note of the following:

• The abstract contains the numerical results of the experiment.
• The report is written clearly and concisely.
• Pages are numbered.
• Calculations are done correctly, with units shown at each step. Trivial calculations may be omitted.
• Extensive calculations are placed in an appendix to make report more readable.
• Numerical results are not reported to more significant figures than is justified.
• Appropriate Confidence limits are given with all results.
• No parameter should ever be calculated without it being very clear in the paper just what the parameter means.
• All graphs are properly titled, labeled and numbered.
• All tables have titles and are numbered.
• Comparisons with appropriately referenced literature values are made. References to the original literature should be made whenever possible.
• Assistance of others is acknowledged.
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REPORT GRADING SHEET

Experiment_________________ Name_________________

1. (12 points) ABSTRACT and PURPOSE
	SCORE____
2. (10 points) EXPERIMENTAL PROCEDURE
	SCORE____
3. (15 points) DATA ANALYSIS INCLUDING EXAMPLE CALCULATION
	SCORE____
4. (15 points) FIGURES (GRAPHS, PICTURES), TABLES
	SCORE____
5. (15 points) ERROR ANALYSIS and DISCUSSION, INCLUDING PROPAGATION OF ERRORS WHERE APPROPRIATE (IN AN APPENDIX).
	SCORE____
6. (15 points) DISCUSSION and CONCLUSIONS EXPLAIN RESULTS, ANSWER QUESTIONS IN TEXT, ETC.
	SCORE____
7. (6 points) REFERENCES
	SCORE____
8. (12 points) STYLE, GRAMMAR, FORMAT, ETC.
	SCORE____

                                                                                                                                 LATE PENALTY____

                                                                                                             REPORT GRADE____
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GRADING SHEET FOR LABORATORY NOTEBOOK
CRITERIA	WEIGHT	x SCORE (0-10)	= POINTS
Notes in black, ball-point pen?	2	9	18
Legible handwriting?	3	8	24
Up-to-date table of contents?	4	-	-
Each entry signed and dated: e.g., Thurs. 8 September 2001	5	-	-
Each section has clear heading describing the work reported therein?	7	-	-
Are entries written in first person, stating who did the work?	7	-	-
Is the work described completely so it can be understood without explanation?	10	-	-
Is the researcher "thinking in the notebook?"	7	-	-
Is there evidence of an attempt to "sort the experiment out" during lab?	8	-	-
Are units and significant figures appropriate?	10	-	-
Are all experiments included?	10	-	-
TOTAL POINTS			730

Note: Example points in italics.
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ASSIGNMENT #1

Use of a computer is required for completing your reports as much as possible, and you will be required to do spreadsheets on the computer because of the ease and accuracy. You will find that tables and text are much easier to do on computer than by hand, and have the advantage of allowing quick rewrites, spelling checks, etc., all leading to a better report. Graphs and equations are probably easier to do neatly by hand until you become more familiar with the computer. Remember readability is the key.

Procedure:

The following assignment is to be completed before the next laboratory meeting time, but preferably today. You should have your own Macintosh or PC 31/2 inch floppy disc to store your data on. Work through the two tutorials in Computer labs in Blackington (230 always open). Both assignments are due next meeting time in hard copy form and stored on your disc. Hint: Greek letters are found on the symbol font. Tables are best made starting with the table command.

A. Spreadsheet: Complete the Tutorial on the Excel "spreadsheet", or any equivalent spreadsheet program, then use a spreadsheet to complete the following exercise:

Calculate the energy per photon and the energy per mole of photons for radiation of wavelength, l = (a) 600.0 nm (red), (b) 550.0 nm (yellow), (c) 400.0 nm (blue), (d) 200.0 nm (ultraviolet), (e) 150 pm (X-ray), (f) 1.00cm (microwave). Use appropriate significant figures throughout.

Do it as a spreadsheet, not a table. Enter the constants in equations to construct the spreadsheet using the following relationships, or put them in an absolute address and include in your formula. You do not need to print out units in your equations, just use units in the headings of each column, that is l /nm, E/J, and E/(kJ mol^-1).  Use the equation

E =  = (energy per photon)

where h = 6.62608 x 10^-34 J s, c = 2.99792 x 10⁸ m s^-1 , N_A = 6.02214 x 10²³ mol^-1.  Use the Chart Wizard to make a separate chart of E vs. wavelength.  Make the data fill the graph by adjusting the axis min/max values.  Save as a chart. Add a trendline under Data and choose the options for a regression fit and R-square value.  Find the trendline that gives a value of R = 1.000.

B. Word processing: Complete the Tutorial on Microsoft Word, or any other word processing software, then type in the following document with the same tabs, etc., using Geneva font (it prints well):

THERMOCHEMISTRY

INTRODUCTION

Chemical reactions useful to create new substances but also to generate heat (fuels) and other forms of energy such as electricity and mechanical.

What drives a gasoline engine?

2 C₈H₈(g) + 21 O₂(g) 16 CO₂(g) + 10 H₂O(g)

Moles of gas: 26-23 = 3 or 3/23 = 13% increase.

Therefore, it must be heating of the gases that causes expansion on explosion, unlike black gunpowder, where 32 moles gas are formed per mole of reaction!

DEFINITIONS

THERMOCHEMISTRY--thermo (heat) + chemistry (stoichiometry)

SYSTEM--the substance or mixture undergoing chemical change.

SURROUNDINGS--everything else in vicinity.

Eg.: bullet fired from gun: system is the gunpowder, surroundings the barrel, shell, bullet.

TABLE 1: PERMISSIBLE VALUES OF QUANTUM NUMBERS

SHELL	SUBSHELL	SUBSHELL NOTATION	ORBITAL	MAX. NO. ELECTRONS
n	l		ml
1	0	1s	0	2
2	0	2s	0	2
2	1	2p	-1,0,+1	6
3	0	3s	0	2