Question

3. A solution that may contain any of the group III cations. Treatment of the solution with CIO in alkaline medium yields a yellow solution and a colored precipitate. The acidified solution is unaffected by treatment with NH,OH. The colored precipitate dissolves in nitric acid; addition of excess NH,OH to this acidic solution produces only a blue solution. Which group III ions are present? Which are absent? Which are in doubt? How would you remove all doubt?

Answer 1

Solution:

Given that:

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