Chloric acid

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Chloric acid
Chloric acid
Chloric acid
Names
Other names
Chloric(V) acid
Identifiers
7790-93-4
ChemSpider 18513
Jmol-3D images Image
Properties
HClO3
Molar mass 84.45914 g mol−1
Appearance colourless solution
Density 1 g/mL, solution (approximate)
>40 g/100 ml (20 °C)
Acidity (pKa) ca. −1
Structure
pyramidal
Hazards
Main hazards Oxidant, Corrosive
Safety data sheet See: data page
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g., phosphorus Special hazard OX: Oxidizer. E.g., potassium perchlorateNFPA 704 four-colored diamond
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
Supplementary data page
Refractive index (n),
Dielectric constantr), etc.
Thermodynamic
data
Phase behaviour
solid–liquid–gas
UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Chloric acid, HClO3, is an oxoacid of chlorine, and the formal precursor of chlorate salts. It is a strong acid (pKa ≈ −1) and oxidizing agent.

Properties[edit]

Chloric acid is thermodynamically unstable with respect to disproportionation.

Chloric acid is stable in cold aqueous solution up to a concentration of approximately 30%, and solution of up to 40% can be prepared by careful evaporation under reduced pressure. Above these concentrations, chloric acid solutions decompose to give a variety of products, for example:

8HClO3 → 4HClO4 + 2H2O + 2Cl2 + 3 O2
3HClO3 → HClO4 + H2O + 2 ClO2

Hazards[edit]

Chloric acid is a powerful oxidizing agent. Most organics and flammables will deflagrate on contact.

Production[edit]

It can be prepared by the reaction of sulfuric acid with barium chlorate, the insoluble barium sulfate being removed by precipitation:

Ba(ClO3)2 + H2SO4 → 2HClO3 + BaSO4

Another method is the heating of hypochlorous acid, producing chloric acid and hydrogen chloride:

3HClO → HClO3 + 2 HCl

See also[edit]

References[edit]