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: Selecting the method used to create dilutions (volume vs. weight) and choosing elements used to analyze and identify "shavings"
Chemist: Making dilutions on the fly as Manager innovates
Software: Running the lab robot, all spreadsheets, and exchanging data
Hardware: Running the Buck AA Spectrometer and the lab robot


A classic assembly line crisis has occurred. A pill coating machine has either malfunctioned, or the pill mix has been adulterated. The only evidence of what could have happened are few tenths of a gram of "shiny" bronze-like, metallic shavings. If the shavings are portions of an adulterant, then the entire assembly line must be shut down, a day or two layoff of the next shift done, throwing people out of work and leading to probable employee grievances. If the shavings are, however, portions of a standard bronze alloy, then the problem it more likely from a bronze bearing or bushing failure. The objective is to determine if the shavings are from standard bronze alloys, or not.


Part of the interview occurs in public view on the day of the lab, in front of Upper Management's standards cabinet, if Manager concludes that the shavings are in fact from one of the standard bronze alloys. The rest is to present the experimental design, all lab records, any memos, and

Manager’s justifications for deciding whether or not the line should be shut down, and preparing enough material for Upper Management that he can handle any employee grievances. Experiment design, rationalization behind solution preparation method (weight vs. volume) and data quality are crucial. Do the experimental results reflect the choice of dilution method as being the better procedure? Bronze misidentifications need to be dissected for cause.

AA Cu curve