Sulfuric acid is a historical name: vitriol.The study of acid began in ancient times, in his writings, it is described: the Greek physician Dioscorides, a Roman naturalist Pliny the Elder, Islamic alchemist Geber, Razi and Ibn Sina and others.The Sumerians existed list of vitriol are classified by the color of the substance.In our time, the word "vitriol" combines crystal hydrates of divalent metal sulfates.
In the 17th century, the German-Dutch chemist Johann Glauber received the sulfuric acid by burning sulfur and potassium nitrate (KNO3) in the presence of water vapor.In 1736, Joshua Ward (a pharmacist from London), this method is used in the production.This time can be regarded as a reference point when a large scale has become produced sulfuric acid.Its formula (H2SO4), as is commonly believed, was established by the Swedish chemist Berzelius (1779-1848) Silent later.
Berzelius using alphabetic characters (designated chemical elements) and lower numerical index (indicated by the number in the molecule, atoms of the species) found that in one molecule contained one atom of sulfur (S), two hydrogen atoms (H) and 4oxygen atoms (O).Since that time become known qualitative and quantitative composition of the molecule, i.e. the language of chemistry described sulfuric acid.
structural formula showing graphically the relative position of atoms in a molecule and the chemical bonds between them (they are usually denoted by lines), informs that in the center of the molecule is a sulfur atom that is double bonded to two atoms of oxygen.With the other two oxygen atoms, each of which is attached a hydrogen atom, the sulfur atom is connected by single bonds.
Properties
Sulfuric acid - a colorless or slightly yellowish, viscous liquid, soluble in water at all concentrations.It is a strong mineral acid.The acid is highly corrosive to metals (concentrated does not react with the iron without heating and passivate it), rocks, animal tissues or other materials.It characterized by high and pronounced hygroscopic properties of a strong oxidizing agent.At a temperature of 10.4 ° C acid solidifies.When heated to 300 ° C almost 99% acid loses sulfur trioxide (SO3).
its properties change depending on the concentration of an aqueous solution.There are common names acid solutions.Dilute acid is considered to be up to 10%.Rechargeable - from 29 to 32%.At concentrations less than 75% (as defined in ISO 2184), it is called the tower.If the concentration of 98%, then it will be a concentrated sulfuric acid.Formula (chemical or structural) in all cases remains unchanged.
When dissolved in concentrated sulfuric acid, sulfur trioxide formed oleum or fuming sulfuric acid, its formula can be written as: H2S2O7.Pure acid (H2S2O7) is solid with a melting point of 36 ° C.Sulfuric acid hydration reaction characterized by the release of heat in large amounts.
dilute acid reacts with metals, in response to which exhibits a strong oxidant properties.This restores the sulfuric acid formed formula substances containing reduced (to 4, 0 or -2), a sulfur atom, may be: SO2, S or H2S.
Reacts with non-metals such as carbon or sulfur:
2 H2SO4 + C → 2 SO2 + CO2 + 2 H2O
2 H2SO4 + S → 3 SO2 + 2 H2O
Reacts with sodium chloride:
H2SO4+ NaCl → NaHSO4 + HCl
It is characterized by an electrophilic substitution reaction of a hydrogen atom attached to the benzene ring of the aromatic compound to the group -SO3H.
Getting
In 1831, contact was patented method of obtaining H2SO4, which is currently the main.Today most of the sulfuric acid is produced using this method.The raw materials used sulphide ore (usually iron pyrite FeS2), which is burned in special furnaces, thereby forming a calcined gas.Since the gas temperature is equal to 900 ° C, it was cooled sulfuric acid with a concentration of 70%.The gas in the cyclone and the electrostatic precipitator is cleaned from dust in washing towers with an acid concentration of 40 and 10% of catalyst poisons (As2O5 and fluorine), wet electrostatic precipitators of acid aerosol.Next, the calcined gas containing 9% of sulfur dioxide (SO2), dried and fed to the contact apparatus.After going through 3 layers of vanadium catalyst, SO2 is oxidized to SO3.To dissolve the formed sulfur trioxide, concentrated sulfuric acid is used.Formula solution of sulfur trioxide (SO3) in anhydrous sulfuric acid is H2S2O7.In this form of oleum in steel tanks is conveyed to the consumer where it is diluted to the desired concentration.
Application
Due to different chemical properties, H2SO4 has a wide range of applications.In the production of the acid as an electrolyte in a lead-acid batteries to manufacture the various cleaners, it is also an important reactant in the chemical industry.It is also used in the production of alcohols, plastics, dyes, rubber, ether, adhesives, explosives, soap and detergents, pharmaceuticals, pulp and paper, oil.
