Discussion Overview
The discussion revolves around the use of manganate(VII) versus dichromate(VI) in titrating Fe(II) in volumetric analysis. Participants explore reasons for the preference of one reagent over the other, touching on aspects such as color change, electrode potential, and solubility.
Discussion Character
- Homework-related
- Exploratory
- Debate/contested
Main Points Raised
- One participant suggests that the sharper color change with manganate(VII) (from purple to mostly colorless) is a reason for its preference over dichromate(VI) (orange to green), although they express uncertainty about this point.
- Another participant notes that the emf of the manganate reaction (+0.75V) is higher than that of dichromate (+0.56V), questioning whether this implies a faster reaction rate.
- A participant raises a question about the solubility of chromates and dichromates, indicating a potential factor in the choice of reagent.
- There is a discussion about the color of products when using dichromate with HCl, with one participant recalling that the solution would turn green.
- Another participant mentions that iron chromates are likely weakly soluble, which could interfere with the redox reaction, and notes the colors of Cr3+ (green) and Fe3+ (slightly yellow) in this context.
- One participant agrees that the color change when chromate is added in excess makes sense.
Areas of Agreement / Disagreement
Participants express various viewpoints regarding the reasons for using manganate(VII) over dichromate(VI), with no consensus reached on the definitive advantages or disadvantages of either reagent. Multiple competing views remain regarding color changes, solubility, and reaction dynamics.
Contextual Notes
Participants express uncertainty about the implications of emf values and the solubility of chromates, indicating that these factors may depend on specific conditions or definitions not fully explored in the discussion.