Discussion Overview
The discussion revolves around calculating the solubility of lead iodide (PbI2) in a solution of aluminum iodide (AlI3) with a concentration of 0.300m. Participants explore the dissociation equations, equilibrium expressions, and the implications of the presence of excess iodide ions on solubility.
Discussion Character
- Homework-related
- Mathematical reasoning
- Technical explanation
Main Points Raised
- One participant presents a dissociation equation for PbI2 and suggests writing an equilibrium expression based on the solubility product constant (Ksp).
- Another participant notes that dissolving PbI2 in the presence of excess I- ions affects the molarity of I in the equilibrium expression.
- A participant questions the correctness of the dissociation equation proposed by the original poster, stating that combining two separate reactions into one equation is not valid.
- The original poster later claims to have calculated a final solubility of 6.67M for PbI2, seeking validation of this result.
- Another participant challenges this result, asserting that 6.67M is too high for a substance that is known to be very weakly soluble.
Areas of Agreement / Disagreement
Participants express differing views on the correctness of the dissociation equation and the calculated solubility of PbI2. There is no consensus on the final answer, and the discussion remains unresolved regarding the accuracy of the calculations and the approach taken.
Contextual Notes
Participants have not fully clarified the assumptions regarding the dissociation of AlI3 and its impact on the concentration of iodide ions. The calculations presented are based on incomplete information and may depend on additional context regarding the solubility of PbI2.