Chloric acid
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| Chloric acid | |
|---|---|
| |
| General | |
| Other names | Chloric(V) acid |
| Molecular formula | HClO3 |
| Molar mass | 84.45914 g/mol |
| Appearance | colourless solution |
| CAS number | [7790-93-4] |
| Properties | |
| Density and phase | ca. 1 g/ml, solution |
| Solubility in water | >40 g/100 ml (20 °C) |
| Acidity (pKa) | ca. −1 |
| Structure | |
| [[Orbital hybridisation#Molecule shape| pyramidal | |
| Dipole moment | ? D |
| Hazards | |
| MSDS | External MSDS |
| Main hazards | Oxidant |
| NFPA 704 | |
| Supplementary data page | |
| Structure and properties | n, εr, etc. |
| Thermodynamic data | Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| Related compounds | |
| Other anions | Bromic acid Iodic acid |
| Other cations | Ammonium chlorate Sodium chlorate Potassium chlorate |
| Related compounds | Hydrochloric acid Hypochlorous acid Chlorous acid Perchloric acid |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references | |
Chloric acid, HClO3, is an oxoacid of chlorine, and the formal precursor of chlorate salts. It is almost a strong acid (pKa ≈ −1) and oxidising agent.
It is prepared by the reaction of sulfuric acid with barium chlorate, the insoluble barium sulfate being removed by precipitation:
- Ba(ClO3)2 + H2SO4 → 2HClO3 + BaSO4
It is stable in cold aqueous solution up to a concentration of approx. 30%, and solution of up to 40% can be prepared by careful evaporation under reduced pressure. Above these concentrations, and on warming, chloric acid solutions decompose to give a variety of products, for example:
- 8HClO3 → 4HClO4 + 2H2O + 2Cl2 + O2
- 3HClO3 → HClO4 + H2O + ClO2
The decomposition is controlled by kinetic factors: indeed, chloric acid is never thermodynamically stable with respect to disproportionation.
[edit] References
- Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.). Oxford:Butterworth-Heinemann. ISBN 0-7506-3365-4.
- King, R. B. (Ed.) (1994) Encyclopedia of Inorganic Chemistry, Vol. 2, p. 658. Chichester:Wiley. ISBN 0-471-93620-0
[edit] External links
ja:塩素酸 pl:Kwas chlorowy(V) ru:Хлорноватая кислота sr:Хлорна киселина nl:chloorzuur
