THE CASE OF THE PROBLEM PATENT
Names
An Acid-Base Investigation
Background
Jonson Pharmaceuticals is working on a drug to reduce the effects of the flu. Three
different research groups in the company are working on the same problem. A number of
drugs have been tested, and one drug was successful. However, the label fell off of this
sample, so the pharmaceutical company is not sure which group made the effective drug.
This drug is currently labeled “Unknown”. Your forensics consulting company has
been called in to determine which research group created the effective drug, which will then
be patented and sold.
When the three research groups were first organized, the supervising lab manager gave
each group a different purple dye to use in making their compound. If the dye can be correctly
identified, the group who made the successful drug can be identified.
Purpose
You will complete all your analysis and a write a summary report (a.k.a. a laboratory report)
to the president of Jonson Pharmaceuticals (me) identifying the research group that created the
drug. This report must by typed and include this sheet (5pts), data tables (10 pts), calculations
(15 pts), a data analysis section (10 pts), your findings (10 pts), and the answer to Part 3 (25 pts)
Materials
dye from “Superbad” Research Team
1 M HCl
1 M NaOH
dye from “O’doyle Rules” Research Team
1 M weak acid
1 M weak base
dye from “Weekend Playahs” Research Team
“Unknown”, effective drug with dye
Test tubes and rack
pH meters
Prelaboratory Questions
1. Calculate the pH of a solution which
2. Calculate the [H3O+] of a
has a [H3O+] of 6.7 x 10-8 M
solution of pH 4.3
PART 1: Using the materials provided, calculate the [H3O+] for each dye (S, O, and W),
HCl, NaOH, weak acid and weak base, unknown, and water (control). Create your own
data table and keep track of your observations and calculations, if any.
PART 2: In order for a dye to have practical uses, it must be stable under a variety of
conditions, such as exposure to sunlight, high temperatures, or a change in pH. Using
the materials provided, figure out if the color of each dye, including the dye in the
Unknown, is affected by a change in pH. Create your own data table and keep track of your
observations and calculations, if any.
PART 3: Jonson Pharmaceuticals is looking to hire more chemists, so they also ask you
to solve the following problem as a job application. Here is the question:
“During your investigation of this task, you suddenly time-warp back to the 1300’s and
accept a job as the village chemist. One day a man brings you a harmful water sample from his
well. He wants to know if it is acidic or basic, so that he can neutralize it.”
“This would be easy if you had your pH meter. However all you have to solve this
problem are your data tables and the 3 dyes used by the 3 research teams. Determine the
approximate pH and [H3O+] of the water sample.”
Data Analysis: Summarize your data and explain how you collected it (about 10
sentences). Should any of the dyes NOT have been used by the research teams? Explain.
Findings: Which research group created the successful drug, and how do you know
this? Be sure that you substantiate your claim with scientific evidence (about 10
sentences).
Jonson Pharmaceuticals Application
Discuss how you solved the problem in Part 3, including your choices of data collection
methods and your results. What are the approximate pH and [H3O+] of the water
sample of the man’s well-water?