| Popis: |
With the intention of doing a study of the CrO/Cr2O equilibrium in aqueous solution, we have carefully re-examined the Raman spectra of CrO, Cr2O and ClCrO. Diluting stepwise an aqueous solution of CrO ion we have showed the non-existence of the HCrO species which was previously considered to exist in such systems. By studying the effect of pH on the Raman spectra we calculated the constant for the equilibrium: 2 CrO + 2H+ ⇌ Cr2O + H2O to be log β22=13.77±0.02 (20°C and KNO3 0.8 M). Using this value of the constant, we were able to establish the distribution diagram of the CrO and Cr2O species versus pH. |
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