Hydrogen Fluoride HF
Under Normal Conditions, It Is A Colorless, Toxic Gas With A Pungent Odor. Easily Soluble In Water, Infinitely Miscible With Water To Form Hydrofluoric Acid.
Hydrogen Fluoride Is Hygroscopic
Smoke After Absorbing Moisture In The Air. Melting Point Is Minus 83.37 Degrees Celsius, Boiling Point Is 19.51 Degrees Celsius. The Gas Density Is 0.922 Kilograms Per Cubic Meter And The Relative Molecular Weight Is 20.008 In The Standard State. Hydrogen Fluoride Has Associative Properties Due To Intermolecular Hydrogen Bonds And Exists As An Associated Molecule HF.
At Normal Temperatures And Pressures, Hydrogen Fluoride Molecules Are A Mixture Of HF2 And HF3. Above 82 Degrees Celsius, Gaseous HF Basically Becomes A Single Molecule State.
Due To The Association Between Molecules, The Boiling Point Of Hydrogen Fluoride Is Much Higher Than That Of Other Hydrogen Halides, And It Exhibits Some Abnormal Properties.
Hydrogen Fluoride Is Highly Reactive And Reacts With Many Compounds
As A Solute, It Is A Weak Acid In An Aqueous Solution, And As A Solvent, It Is A Strong Acid, Equivalent To Anhydrous Sulfuric Acid. It Can React With Oxides And Hydroxides To Form Water, And Can Undergo Substitution Reactions With Metal Compounds Of Chlorine, Bromine, And Iodine. Can React With Most Metals, React With Some Metal Phenols LNI, Ng, Etc. To Form A Fluoride Protective Film Insoluble In HF.
Copper Is Quickly Corroded By HF In The Presence Of Oxygen, But Does Not React When There Is No Oxidant. Some Alloys, Such As Monel, Have Good Corrosion Resistance To HF, But Stainless Steel Has Poor Corrosion Resistance. When Not Too High, Carbon Steel Also Has Sufficient Corrosion Resistance.
Hydrogen Fluoride Is Similar To Water
The Dielectric Constant Is 83.6 At 0 Degrees Celsius. It Is An Ideal Solvent And Can Undergo Solvolysis Reaction With Solute. In Addition, Anhydrous Hydrogen Fluoride Has A Strong Proton-Donating Ability And A Strong Dehydration Ability. Wood And Fibers Are Carbonized Immediately Upon Contact With Them, And Polymers Are Formed After Contact With Organic Compounds Such As Alcohols, Aldehydes, And Ketones For Dehydration. Their Dehydration Capabilities Are Weaker Than Those Of Sulfuric Acid And Phosphoric Acid.
Hydrogen Fluoride Is Nonflammable
However, It Is Dangerous When Mixed With Some Substances Such As Sodium, Calcium Oxide, Potassium Nitrate, Sodium Chlorate, Etc. Hydrogen Fluoride Is A Basic Chemical Product, And Anhydrous Hydrogen Fluoride Is The Raw Material For Electrolytic Production Of Elemental Fluorine.
In The Chemical Industry, It Is Widely Used To Replace Chlorine In Hydrogen Halides By Fluorine To Produce Chlorofluorocarbons, Such As Difluorodichloromethane F12 And Difluorochloromethane F22.
In The Petrochemical Industry, It Is Used As A Liquid Catalyst For Aromatic Hydrocarbons, Aliphatic Compounds, And Alkylated High-Octane Gasoline.
In The Electronics Industry, Anhydrous Hydrogen Fluoride Is Used As A Raw Material For Electrolytic Synthesis Of Nitrogen Trifluoride, As A Solidifying Agent In Semiconductor Manufacturing Processes, Etc.
In Addition, Hydrogen Fluoride Is Used In Industrial Production Of Hydrofluoric Acid, Production Of Inorganic Fluoride Oil Processing, Metal Processing And Etching Agents In The Glass Industry, Etc.
