Discussion Overview
The discussion revolves around calculating the pH of a 8.57x10-10M HNO3 solution, focusing on the complexities introduced by the low concentration of the acid and the need to consider equilibrium effects. It encompasses homework-related queries and technical reasoning regarding acid dissociation and hydronium ion concentration.
Discussion Character
- Homework-related
- Technical explanation
- Debate/contested
Main Points Raised
- One participant suggests that the hydronium ion concentration should be the sum of the concentration from nitric acid and the concentration from water, leading to a calculated pH of 6.99.
- Another participant questions the validity of the initial calculation, noting that a pH above 7 is incorrect for an acid solution.
- A different participant asserts that the presence of nitric acid will result in a pH below 7, emphasizing the need to consider both the dissociation of water and the acid.
- One participant explains that the dissociation of water produces equal concentrations of H3O+ and OH-, and suggests using these to find the equilibrium constant (Kw) to solve for pH.
- Another participant states that the conventional pH calculation method is not applicable for concentrations below 10-6 M, indicating that equilibrium must be considered in such cases.
Areas of Agreement / Disagreement
Participants express disagreement regarding the correct approach to calculating the pH, with some asserting the need for equilibrium considerations while others present differing views on the contributions of hydronium ions from both the acid and water.
Contextual Notes
Limitations include the assumption that the dissociation of water can be neglected at higher concentrations, and the unresolved mathematical steps involved in applying equilibrium principles to this specific concentration of nitric acid.