Fluoroantimonic acid is widely recognized as the strongest acid known.
The Reigning Champion: Fluoroantimonic Acid
Based on its ability to donate a proton (H⁺), fluoroantimonic acid holds the title of the strongest acid in the world. This remarkable compound is significantly stronger than common strong acids like sulfuric acid (H₂SO₄).
Composition and Properties
As detailed in research and confirmed, fluoroantimonic acid, also known by its chemical shorthand HFSbF₆, is not a single molecule but a mixture.
- It is created by combining hydrogen fluoride (HF) and antimony pentafluoride (SbF₅).
- The reaction between these two substances produces a substance with extraordinary acidity.
- Visually, it is described as a colourless fuming liquid.
The incredible strength of fluoroantimonic acid comes from the ability of the SbF₆⁻ anion to stabilize the positive charge after the hydrogen ion (proton) is donated. This weak interaction allows the acid to donate its proton extremely easily, making it a superacid.
Why is it so Strong?
Acids are measured by their acidity function, often using the Hammett acidity function (H₀) for superacids, as the pH scale is inadequate. Fluoroantimonic acid has an incredibly low (highly negative) H₀ value, indicating its immense proton-donating power. Its strength allows it to protonate even weak bases that are typically considered non-basic.
