A N A L Y T I C A L   C H E M I S T R Y  2 5 6
R O L E - P L A Y I N G   L A B
1998-1999 Academic Year
©Prof. John P. Walters
St. Olaf College
Northfield, MN 55057

Introduction to Role-Playing and Laboratory Computing
Defining the Kinds of Role-Playing Responsibilities
Round-Robin Certification of Laboratory Glassware
Production Quality Control Lead Analysis

Statistical/Chemical Evaluation of Lead Data

Semi-Automated Weak Acid Titration
Graphical Analysis of Weak Acid Titration
Designing a Mock Robot Experiment
Executing the Mock Robot Experiment
The Incredible Edible Easter Egg Grass Advertising Dilemma
The Downsizing Dilemma
The Broken Pill Coating Machine Assembly Line Shutdown Dilemma
The Instrument Purchase Payment Release Dilemma


Manager: Defines how to do the round robin accuracy determination and schedules when Chemist and Hardware do the lead AA analysis
Chemist: Finishes forming, digesting, and drying lead precipitates, weighsprecipitates, and then prepares all solutions for lead AA analysis
Software: Builds and fills all spreadsheets for round robin determinations and AA projects, works with Hardware to obtain stable cooling curves
Hardware: Filters and weighs precipitates, and operates AA


The primary objective is to dry and weigh the lead precipitates, calculate the percent lead in the class sample, and get all of the data onto the Analytical Chem. Server for all other Managers and Software people to use in doing round robin accuracy determination of the master sample by t-test statistics. A second objective is to use the AA to test lead results by another method. A third objective is to learn how to prepare solutions by different methods (volume/volume, weight/volume, volume/weight, weight/weight) and last, to learn how to do a standard addition method to a sample whose matrix is unknown.


Manager should come to the interview prepared to show how the precipitate data were used in round robin testing to arrive at an agreed upon class average value for the percent lead in the master sample. Emphasis on cooperation between Companies in getting the data to each Manager so that round robin tests could be done is appropriate for discussion. Of special interest are the results obtained with the AA as regards Manager’s own data and the comparison of those data with others in the class. Manager should be prepared to explain what the method of standard additions does, and how it is used to compensate for samples whose matrix is unknown. A professional interview presupposes good communication between Companies, and Manager should be prepared to discuss how she or he aided this process.

lead results