Karita, S. and Kaneta, T. “Acid-base titrations using microfluidic paper-based analytical devices.” Analytical Chemistry 2014, 86, 12108–12114.
- What is a primary standard and how are they commonly used in titrations?
- What primary standard is most often used for the standardization of aqueous bases (e.g., NaOH)? What primary standard is most often used for the standardization of aqueous acids (e.g., HCl)?
- What is a microfluidic device?
- Phenolphthalein is commonly used as an indicator for acid-base titrations. What color is it in solution at each pH listed below?
- <0 b. 0–8.2 c. 8.2–12 d. >13
Please read the assigned article and discuss the following with your group members.
- How does the µPAD described overcome the typical disadvantages of acid-base titrations?
- How did the authors have to modify the device to detect acids instead of bases?
- Why did the authors choose phenolphthalein as the indicator for this device? Under what circumstances will this indicator not work?
- One disadvantage of the µPAD is limited precision in terms of the number of significant figures one can report in the concentration. For a traditional titration, what is the limiting factor for the precision of the measurement? For this new µPAD, what is the limiting factor?
- Propose a means by which you could increase the precision of the measurement.
- What dictates the range of concentrations that can be detected by the µPAD?