The kinetics of the photoaquation of the octacyanomolybdate(IV) ion in aqueous solution were studied by potentiometric and spectrophotometric methods. In an alkaline medium a simple scheme analogous to the photoaquation of the hexacyanoferrate(II) ion describes the process. The values of the constants of the kinetic equation are: (Φ = 1.0, k8 = (6.55 ± 0.8) x 10-9 s-1, and k-8 = (7.88 ± 0.5) x 10-2 mol-1 dm3 s-1 (pH = 10.5). The reversibility of the photoaquation is also explained by the scheme. A simultaneous measurement of free cyanide ion concentration and the absorbance at 512nm shows that the red coloured transition product is a heptacyano complex.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry