Aqueous fluoroxysulfate: decomposition and some chemical reactions

Journal Article · Sat Nov 01 04:00:00 EST 1980 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic50213a009· OSTI ID:6626590

Thompson, R C ^[1]; Appelman, E H

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1. Univ. of Missouri, Columbia

Aqueous SO/sub 4/F/sup -/ decomposes to form O/sub 2/, H/sub 2/O/sub 2/, and HSO/sub 5//sup -/. At 15/sup 0/C in 0.01 M HC1O/sub 4/ the first-order rate constant k = 3.6 x 10/sup -4/s/sup -1/, ..delta..H/sup + +/ = 16.8 +- 0.4 kcal/mol, and ..delta..S/sup + +/ = -15.7 +- 1.5 cal/(mol deg). The H/sub 2/O/sub 2/ and O/sub 2/ products both contain one oxygen atom from solvent and one from the fluoroxysulfate. The HSO/sub 5//sup -/ product also contains an atom of solvent oxygen in its terminal peroxide position. A mechanism is proposed in which the rate-determining steps are the interaction of SO/sub 4/F/sup -/ with water fo form HSO/sub 5//sup -/ and H/sub 2/O/sub 2/. The H/sub 2/O/sub 2/ probably interacts further with SO/sub 4/F/sup -/ by means of a free-radical chain reaction to produce O/sub 2/. Fluorosulfate ion, SO/sub 3/F/sup -/, appears to be formed only in the oxygen-transfer step that produces H/sub 2/O/sub 2/. Chlorite ion is rapidly oxidized to C1O/sub 2/ by SO/sub 4/F/sup -/ in accordance with the rate law -d(SO/sub 4/F/sup -/)/dt = k/sub ClO/sub 2//sup -//(ClO/sub 2//sup -/)(SO/sub 4/F/sup -/). In acid solution at 14.7/sup 0/C, k/sub ClO/sub 2//sup -// = 1.8 x 10/sup 4/ L/(mol s), ..delta..H/sup + +/ = 7.3 +- 0.6 kcal/mol, and ..delta..S/sup + +/ = -14 +- 2 cal/(mol deg). The oxidation of Co(NH/sub 3/)/sub 5/ClO/sub 2//sup 2 +/ by SO/sub 4/F/sup -/ produces ClO/sub 2/ and a mixture of Co(NH/sub 3/)/sub 5/F/sup 2 +/ and Co(NH/sub 3/)/sub 5/H/sub 2/O/sup 3 +/. The oxidation of Cr/sup 2 +/ by SO/sub 4/F/sup -/ produces 42 to 47% Cr/sup 3 +/ and 41 to 45% CrF/sup 2 +/, the balance consisting of polynuclear Cr(III) species. The oxidation of I/sup -/ to I/sub 2/ by SO/sub 4/F/sup -/ consumes no acid and hence does not produce SO/sub 3/F/sup -/. These rapid reactions may be interpreted in terms of mechanisms involving either 1- or 2-equiv oxidation in the rate-determining steps. Oxygen transfer does not appear to be significant, but fluorine transfer is obviously involved at least in the oxidation of Cr/sup 2 +/ and Co(NH/sub 3/)/sub 5/ClO/sub 2//sup 2 +/.

• OSTI ID: 6626590
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 19:11; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
AQUEOUS SOLUTIONS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DISPERSIONS
ELEMENTS
EXPERIMENTAL DATA
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HALOGENS
HYDROGEN COMPOUNDS
HYDROGEN PEROXIDE
INFORMATION
IODINE
KINETICS
MIXTURES
NONMETALS
NUMERICAL DATA
OXYGEN
OXYGEN COMPOUNDS
PEROXIDES
REACTION KINETICS
REDOX REACTIONS
SOLUTIONS
SULFATES
SULFUR COMPOUNDS
TABLES