Hf Weak Or Strong Acid

Hydrofluoric Acid (HF) Molecule — Hydrofluoric acid (HF) is a weak acid mainly because it forms stable species afterward information technology dissociates.

Hydrofluoric acid or HF is an extremely powerful, corrosive acid. Even so, it's classified equally a weak acid rather than a strong acid. This makes HF the only hydrohalic acrid that isn't classified as a stiff acid (east.1000., HCl, HBr, Howdy).

Why Hydrofluoric Acrid Is a Weak Acid

The simple reason hydrofluoric acid is a weak acid is because it does not completely dissociate into its ions in h2o (the definition of a potent acrid). Initially, HF actually does dissociate nigh completely:

HF + H₂O ⇆ H₃O⁺ + F^–

However, afterward the acid dissociates, it participates in other reactions with itself and with h2o. The behavior of hydrofluoric acid greatly depends on its concentration in water. The hydronium cation and fluoride anion are strongly attracted to one some other and form H_iiiO⁺ · F^–. The chemical bail in this species is strong enough to limit acidity, so hydrofluoric acid is a very weak acid in dilute solution.

Full-bodied HF solutions deport much similar a potent acid. This is due to homoassociation, in which a chemic bail forms between a base of operations and conjugate acrid:

3 HF ⇆ H₂F⁺ + HF₂ ^–

Hydrogen bonding between hydrogen and fluorine stabilizes the FHF^– bifluoride ion. Hydrogen bonding besides causes HF to have a college humid point than the other hydrogen halides.

Is HF Polar?

Two factors play into acid strength: atom size and the polarity of the H-A bond (where A is the acid). Fluorine is highly electronegative, and so the bond in HF is a polar covalent bail. The more than polar a bond is, the easier it is to remove the proton or hydrogen from the acid. Then, hydrochloric acid (HCl) is a stronger acid than hydrobromic acid (HBr). Based but on its polarity, one might wait HF to exist stronger than HCl. Just, HF participates in reactions after dissociation that make it a weaker acid!

Weak only Unsafe

Hydrofluoric acid burn on skin — Hydrofluoric acid causes a chemical burn and then poisons deeper tissues. ( Dr. Watchorn )

Although HF is a weak acrid, it is highly corrosive. It attacks glass, even in dilute solution, so it must exist stored in plastic containers. It'south chancy to work with for a few reasons. First, HF interferes with nerve function, so exposure isn't immediately painful like information technology would be with other acids. Second, information technology'south captivated through tissue, and so it does more than produce a chemic fire on peel or mucous membranes. Ultimately, the acid works its style deeper into tissues, causing bone harm and fluid buildup in the lungs. A hydrofluoric acid burn might non seem serious, but it requires firsthand attention.

References

Favre, Henri A.; Powell, Warren H., eds. (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. Cambridge: The Purple Society of Chemistry. ISBN 9781849733069.
Giguère, Paul A.; Turrell, Sylvia (1980). "The nature of hydrofluoric acrid. A spectroscopic study of the proton-transfer complex H₃O⁺…F⁻". J. Am. Chem. Soc. 102 (17): 5473. doi:ten.1021/ja00537a008
Prkić, Dues; Giljanović, Josipa; Bralić, Marija; Boban, Katarina (2012). "Straight Potentiometric Conclusion of Fluoride Species by Using Ion-Selective Fluoride Electrode". Int. J. Electrochem. Sci. 7: 1170–1179.