Fluorosulfuric acid
 Fluorosulfuric acid sample from Sigma-Aldrich.
| |
| Names | |
|---|---|
| IUPAC name
Sulfurofluoridic acid
| |
| Other names
Epoxysulfonyl fluoride
Fluoridosulfonic acid Fluoridosulphonic acid Fluorinesulfonic acid Fluorinesulphonic acid Fluorosulfonic acid Fluorosulphonic acid Monofluorosulfuric acid Sulfuric fluorohydrin | |
| Properties | |
| HFSO3 | |
| Molar mass | 100.06 g/mol |
| Appearance | Colorless liquid |
| Odor | Pungent |
| Density | 1.726 g/cm3 |
| Melting point | −87.5 °C (−125.5 °F; 185.7 K) |
| Boiling point | 165.4 °C (329.7 °F; 438.5 K) |
| Reacts | |
| Solubility | Reacts with alcohols, amines Soluble in glacial acetic acid, ethyl acetate, nitrobenzene Poorly soluble in alkanes |
| Vapor pressure | 2.47 mmHg at 25 °C |
| Acidity (pKa) | -10 |
| Hazards | |
| Safety data sheet | Sigma-Aldrich |
| Flash point | Non-flammable |
| Related compounds | |
| Related compounds
|
Sulfuric acid Chlorosulfuric acid |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Fluorosulfuric acid or sulfurofluoridic acid is one of the strongest commercially available acids, more specifically a superacid. It has the chemical formula HFSO3.
Contents
Properties
Chemical
Fluorosulfuric is one of the strongest known simple Brønsted acids, although carborane-based acids are still stronger. It has an H0 value of −15.1 compared to −12 for sulfuric acid.
Fluorosulfuric acid reacts with water to release sulfuric acid and hydrofluoric acid.
- HFSO3 + H2O → H2SO4 + HF
Physical
Fluorosulfuric acid is a colorless liquid that fumes in air and reacts violently with water.
Availability
Fluorosulfuric acid is sold by chemical suppliers, though it's not easy to acquire.
Preparation
Fluorosulfuric acid is prepared by the reaction of hydrogen fluoride/hydrofluoric acid and sulfur trioxide:
- HF + SO3 → HSO3F
Alternatively, KHF2 or CaF2 can be treated with oleum at 250 °C. After the HF is removed by sweeping with an inert gas, HSO3F can be distilled in a glass apparatus.
Projects
- Make magic acid
- Compound collecting
Handling
Safety
Fluorosulfuric acid is considered to be highly toxic and corrosive. It hydrolyzes to release HF. Addition of water to this acid is extremely violent, much more that the addition of water to concentrated sulfuric acid.
An antidote for HF, such as calcium gluconate should be present when handling this acid.
Storage
Fluorosulfuric acid should be kept in thick HDPE or PTFE bottles, which are best kept in another larger chemically resistant container, in a dry place, away from moisture and light.
Disposal
The acid can be safely neutralized by strongly dilution with cold water or crushed ice, followed by careful neutralization with a base. Products formed from neutralization are sulfates and fluorides. When neutralized with calcium salts insoluble calcium fluoride salt is precipitated which can be safely disposed. Soluble fluoride salts are toxic and should not be disposed into the environment, instead should be pp to calcium fluoride.
References
Relevant Sciencemadness threads
- Articles containing unverified chemical infoboxes
- Chemical compounds
- Inorganic compounds
- Acids
- Strong acids
- Superacids
- Mineral acids
- Oxoacids
- Fluorine compounds
- Oxidizing agents
- Corrosive chemicals
- Materials unstable in basic solution
- Materials that react with water
- Things that can kill you very quickly
- Hygroscopic compounds
- Liquids
