Calcium Fluoride (fluorspar) is undoubtedly one of the best known and most prized inorganic compounds. Due to its specific properties, it is used for diverse purposes both in households and industrial plants. What are the features of calcium fluoride and where is it used? Let's check that out.
What are fluorides?
Compounds such as calcium fluoride or potassium fluoride belong to a group that is collectively referred to as fluorides. They are inorganic hydrofluoric acid salts containing fluorine. An average consumer would only associate fluorides with fluoridation treatments given prophylactically at schools and kindergartens. Indeed, the compounds have become most popular due to the fluorine content as an ingredient of toothpastes, mouthwashes and tooth enamel strengthening preparations.
Calcium fluoride: production and properties
What is calcium fluoride? The molecular formula of the compound is CaF2 and its systematic name is: calcium difluoride. The substance comes as small, shiny and glassy crystals and is obtained through a reaction of binary hydrofluoric acid with calcium carbonate. CaF2 occurs naturally as a common mineral called fluorite. Fluorite crystals have varying colours, from pink to green and blue.
And what are the physical and chemical properties of calcium fluorite? The compound has a low solubility in water. It is almost insoluble in acids and is a poor electrical conductor. The molecular weight of calcium fluoride is 78.08 g/mol and the density is 3.18 g/cm³ (20 °C). Crystals of CaF2 start to melt at the temperature of 1418 ºC and boil at 2500 ºC . The substance causes corrosion of different materials and reacts with sulfuric acid (VI). Calcium fluoride dissociates into calcium cations and fluorine anions.
Applications of calcium fluoride
Calcium fluoride is widely used in industry and beyond. This chemical compound is mostly fit for the production of hydrogen fluoride, which is used for example in glass etching and yeast production. CaF2 comes in handy as a reagent in chemical laboratories. It is also a valuable raw material used in the production of:
- filters and optical glasses,
- anti-reflection coatings,
- cosmetics,
- (calcium) nitrogenous fertilisers used in agriculture,
- dental preparations and varnishes.
Fluorine and its compounds calcium fluoride and sodium fluoride have a great variety of applications in caries prophylaxis. They are used to produce gels, mouthwashes and pastes that strengthen tooth enamel and protect against acids. The substances are used in stomatology and aesthetic medicine.
Calcium fluoride – harmfulness
Is calcium fluoride harmful? Just like any other chemical substance, calcium fluoride may cause a number of unpleasant ailments of the respiratory and digestive systems, if misused. Under laboratory conditions, the inhalation of CaF2 fumes causes burns of internal organs and even leads to pulmonary oedema. What are the dangers my result from the digestion of calcium fluoride? The crystal causes diffuse poisoning whose symptoms include stomach aches, diarrhoeas and tingling in limbs. The contact of calcium fluoride with the eye mucosa causes redness and burning.
However, note that small doses of CaF2 have no side effects, if used as recommended by manufacturers.
A handful of titbits on calcium fluoride
The fluorite that occurs in nature has several names. Miners call it spar or river spar.
Calcium fluoride is used in the production of dietary supplements that enhance the functioning of all the organs in the body, especially muscles and bones. Powders containing CaF2 are used in treatments to stimulate the immune system and improve the quality of the water-mineral balance of the whole body.