Hydrofluoric acid is often produced in the form of 40% solution, but sometimes there are 50% or 72% solutions.Yet it is called a hydrofluoric acid or aqueous hydrogen fluoride.Her name was formed from the fluorspar from which, in turn, receive hydrogen fluoride.
Hydrofluoric acid - its formula HF.Visually, it is a colorless liquid, has a molecular weight of 20.0063 g / mol and a density - 1.15 g / cm³.It is characterized by temperatures: melting - 83,6 ° C, the boiling point of - 19,5 ° C.It is non-flammable and highly toxic.
What features has the hydrofluoric acid?The formula of this material suggests that it is composed of fluorine and hydrogen.It belongs to the second class of danger, as formed by the dissociation of fluorine toxic and harmful to our environment.
Upon dissolution of the acid in water in an amount of heat is 59.1 kJ / mol.It reacts with many metals, thereby forming fluorides.Interesting is the fact that even a small part of the acid is able to reduce the standard freezing point of water.At low temperatures, hydrogen fluoride forms the following compound with water H2O · HF, H2O and H2O · 2HF · 4HF.
Despite the fact that the hydrofluoric acid refers to the average strength acid, it corrodes and silicate glass containers.Furthermore, it is unique in its class of substance which reacts with silica SiO (2).This oxide, in turn, is the main material used for glass production.Hydrofluoric acid does not affect the paraffin, so it is widely used for its storage.At the present time it is transported and stored only in the plastic package, or made of rubber and lead containers.High concentration (60%) of acid can be carried in strong containers made of steel.
metals that do not dissolve in it, it lead, platinum and gold.Technical hydrofluoric acid contains several impurities, among which the most common are such as Fe, Rb, As, and N2SiF6, SO2.Good cleaning acid is obtained by converting it into potassium difluoride.Next, it is decomposed by heat and hydrogen fluoride is dissolved in water.
When working in laboratories using dishes and containers made of polyethylene and Teflon, and large amounts of hydrofluoric acid stored in steel, dense, sealed tanks, and tanks or bottled ammonia type, which is required to have available protective coloration.
Hydrofluoric acid is dangerous to human health.She has a weak narcotic effect on the psyche.If for any reason it has got into the blood, in this case to avoid severe poisoning to alter the function of the digestive system and pulmonary edema.Even hydrofluoric acid can lead to disruption of the heart and general intoxication.
After contact with skin or eyes, it causes painful burns even at low concentrations.Particularly unpleasant consequences of the penetration of the acid under the fingernails, so work with it only need to wear gloves and a good stretch.
If you still got acid on the skin, then immediately wash it under running water and treat calcium gluconate 2.5% in the form of a gel.But that can not stop, you should consult your doctor immediately.He will appoint an intravenous injection of calcium chloride.
Where is this dangerous acid used?Currently, it is actively used for destroying rocks silicate to dissolve metals such as niobium, tantalum and zirconium.It acts as a catalyst for the hydrogenation and dehydrogenation, as well as in the manufacture of fluoropolymers, halocarbons and fluorosulfonic acid.She found its application in the oil industry.She was treated with oil wells to increase oil production.
