Solubility product of cesium metaperiodate and a nuclear magnetic resonance study of the orthoperiodate-metaperiodate dehydration equilibrium

Abstract

The solubilities of cesium metaperiodate in aqueous solutions of pH 1.3-5.8 have been measured a t 5.0, 25.0, and 40.0". The values calculated for K,,O a t these temperatures were (3.96 =IC 0.17) X(2.24 4 0.07) X 10-3, and (6.53 & 0.04) X 10-3. Evidence was found for a new periodate phase in the system H~O-CSIOC-CSOH, and two previously unreported cesium periodate salts were prepared.The equilibrium constant Kdo and thermodynamic quantities for the reaction HaIOs-(aq) e IO4-(aq) + 2H20(1) have been determined in the temperature range 2-18" by means of a nuclear magnetic resonance technique. The extrapolated value of KdO a t 25' was found to be 29. The corresponding vnltte of AG,!" wts -2 . 0 2~ 0.1 kcal/mole, of AHd" was 14.8 + 1.1 kcal/mole, and of 4.S,io was 50 f 4 eu.At2S0, AGsolno = 1.91 =! = 0.05 kcal/mole, AHSoino = 13.1 kcal/mole, and ASsolno = 37.6 eu.

Mechanism for the Oxidation of Sulfides and Sulfoxides with Periodates: Reactivity of the Oxidizing Species

“…The periodate ion (IO 4 -) and periodic acid (HIO 4 ) are hydrated [57][58][59][60] The equilibrium constant for the dehydration of H 4 IO 6 -(K D = 1/K H = 29 in water at 25°C) was determined by spectroscopic methods. [57,58] The hydration and dehydration of IO 4 -are rapid processes [59] in spite of the large structural changes and the complexity of the reactions.…”

“…[57,58] The hydration and dehydration of IO 4 -are rapid processes [59] in spite of the large structural changes and the complexity of the reactions. Although equilibrium (1) is shifted [57] towards IO 4 -, equilibrium (2) is shifted completely to the right.…”

Complex formation reaction of the iron(iii) hydroxo dimer with periodate ion

“…9- 13 First of all, solid state and dissolved forms of periodate ion are different as it gives rise to the H 5Ϫx IO 6 xϪ family of octahedral species in aqueous solution. [14][15][16][17][18][19][20][21][22][23] Secondly, as will be discussed in this paper, the reaction between periodate ion and Fe 2 (OH) 2 4ϩ is second order with respect to the iron() hydroxo dimer while it is first order with all other ligands. It is also a notable exception that multinuclear complexes were isolated in the solid state from the aqueous iron() periodate ion system earlier.…”

“…In contrast, periodate ion is transformed into octahedral species in water and these species are involved in a number of equilibrium reactions. The thermodynamics and kinetics of these reactions were studied in great detail [14][15][16][17][18][19][20][21][22][23] and interpreted in terms of the following equations: 14-15…”

Heterogenized Water Oxidation Catalysts Prepared by Immobilizing Kläui‐Type Organometallic Precursors

“…The addition of KOH caused an increase of the pH up to 9.60, whereas the injection of NaIO 4 led to a pH of 6.32, which remained substantially unaltered until the end of the run. The observed acidification due to the NaIO 4 addition can be explained by the hydration of IO 4 − with two water molecules, leading to the weak acid H 4 IO 6 − …”