Orthophosphoric acid is a small hygroscopic diamond-shaped crystals that can dissolve in almost any liquid. The melting point of this acid is about 43 ° C.
The use of phosphoric acid
Phosphoric acid has found applications in a variety of industries. More than 90% of all acid goes to the production of fertilizers. Its salts are assimilated by plants in the form of anions. Thanks to phosphorus, plants are able to form fruits and seeds. The sufficient content of this element makes it easier for them to endure the winter, which is especially important for the northern regions.
In the food industry, phosphoric acid is known as the additive E338. It is able to improve the taste of finished products, in particular bakery products, various syrups and drinks. It is used in the manufacture of Coca-Cola.
Orthophosphoric acid is used by dentists when filling teeth to etch enamel. There is one subtlety: acid should not remain on the surface of the tooth after etching, otherwise the filling will soon become unusable. The doctor must remove it before direct filling.
With the help of orthophosphoric acid, coatings (varnishes, enamels) and materials (phosphate foam) are made that are resistant to high temperatures. Wood is treated with solutions of this acid in factories to prevent it from burning.
Getting orthophosphoric acid
Under laboratory conditions, phosphoric acid can be easily obtained by the interaction of phosphorus with a solution of nitric acid (32%). In industry, it is obtained in two ways: extraction and thermal.
The essence of the first method is that natural phosphates (phosphorus oxides) react with various acids (sulfuric, nitric and others) to form pure phosphoric acid. The second method is more costly from an economic point of view. The technology includes the combustion of phosphorus, the absorption of its oxide by water, as well as condensation and subsequent capture of the gas.
The harm of phosphoric acid
Long-term use of products containing the E338 supplement leads to the development of diseases such as osteoporosis and tooth decay. A person suddenly loses weight, frequent vomiting or aversion to food appears. Phosphoric acid disrupts the acid-base balance of the body. Despite this, its use as a dietary supplement is legal in most countries around the world.
Phosphoric acid vapors can cause irritation of the nasal mucosa and eye burns. People working in factories that produce this acid often have conjunctivitis, liver damage, and even pulmonary edema.
