Acid Violet spectral changes

Figure 1. Spectral changes of Acid Violet 19 when the concentration is varied...

If the acidity of the solution is raised to 1-2 M in perchloric acid, aquation beyond the tricyano complex proceeds slowly. The color of the solution gradually reddens, then becomes pink, and finally the pale violet color of the hydrated ion. Again, no one isosbestic point persists throughout these spectral changes. 

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