Discussion Overview
The discussion centers around determining the pH of a strong triprotic acid before titration, specifically in the context of a homework problem involving a 1.5 M solution of the acid and its titration with NaOH. Participants explore the implications of the acid being strong and triprotic, as well as the calculations involved in finding the pH.
Discussion Character
- Homework-related
- Mathematical reasoning
- Conceptual clarification
- Debate/contested
Main Points Raised
- Some participants question what it means for an acid to be "strong," with one suggesting it dissociates completely in solution.
- Participants discuss the number of moles of the acid present, with one stating there are 0.036 moles.
- There is uncertainty regarding the number of protons produced upon dissociation, with conflicting calculations of 0.012 and 0.108 moles of protons being proposed.
- One participant attempts to clarify the concept of triprotic acids, indicating that they contain three hydrogen ions.
- Participants engage in a mathematical analogy to illustrate the calculation of total protons from the moles of acid.
- There is confusion regarding the calculation of pH, with one participant suggesting a concentration of 1.38, which is later challenged as being too high.
- Concerns are raised about the implications of obtaining a negative pH, with one participant asserting that negative pH values are not possible.
- A link is shared to a resource discussing negative pH, indicating some participants are exploring this concept further.
Areas of Agreement / Disagreement
Participants express differing views on the calculation of pH and the implications of negative pH values. There is no consensus on the correct approach to determining the pH of the strong triprotic acid before titration.
Contextual Notes
Participants' calculations depend on their understanding of the definitions of strong acids and triprotic acids, as well as the mathematical steps involved in determining pH. There are unresolved questions regarding the correct concentration and the interpretation of negative pH values.