Production of hydrogen sulphide, its properties, application

In this article we will consider the production of hydrogen sulfide from sulfur. Let us take a closer look at the physical and chemical properties of this substance.

Structure

In order to analyze the main production of hydrogen sulphide, it is necessary to clarify the features of its structure. This substance contains one sulfur atom and two hydrogen. They are non-metals, so covalent polar bonds are formed between the elements . In hydrogen sulphide there is an angular structure. Between sulfur and hydrogen, an angle of 92 degrees is formed, which is slightly less than in water.

Physical properties

The smell of hydrogen sulfide, reminiscent of rotten eggs, is familiar to all. Under normal conditions this substance is in the gaseous state. It has no color, is poorly soluble in water, toxic. On average, at 20 degrees Celsius, 2.4 volumes of hydrogen sulphide will dissolve in the water. At sulphureous water, slight acidic properties are revealed , the dissociation of the substance proceeds stepwise. Poisonous hydrogen sulphide is dangerous even in small doses. The airborne content of about 0.1 percent of hydrogen sulphide leads to paralysis of the respiratory center with loss of consciousness. For example, the legendary naturalist Pliny the Elder died in the 79th century BC precisely from hydrogen sulfide, which was formed during the eruption of Vesuvius.

The cause of the poisoning effect of hydrogen sulphide in its chemical interaction with hemoglobin of the blood. The iron contained in this protein forms a sulphide with hydrogen sulphide.

The maximum allowable concentration in air of hydrogen sulfide is 0.01 mg / l. As an antidote, inhalation of pure oxygen or air is used, in which there is an insignificant amount of chlorine.

Work with hydrogen sulphide implies compliance with certain safety rules. All experiments involving this gaseous substance are carried out in sealed devices and fume hoods.

Methods for producing hydrogen sulphide

What is the receipt of hydrogen sulphide in the laboratory? The most common option is the interaction of hydrogen with sulfur. This chemical reaction refers to a compound that is conducted in a fume hood.

In addition, the production of hydrogen sulphide is possible also in the exchange between solid iron sulfide (2) and a solution of sulfuric or hydrochloric acid. To get this result, it is enough to take a few pieces of sulphide in a test tube that do not exceed the size of a pea. Further, a solution of the acid is added to the tube (up to half the volume), covered with a gas outlet tube. The device is placed under the hood, the tube is heated. The chemical interaction is accompanied by the release of gas bubbles. Such production of hydrogen sulphide allows the creation of a quantity of a substance sufficient to consider its chemical properties.

What other ways are there? The laboratory allows the production of hydrogen sulphide by the interaction of metallic iron (under the extract) with crystalline sulfur, followed by the interaction of the sulfide with sulfuric acid.

Chemical properties

Hydrogen sulphide interacts with the oxygen of the air, it burns with a bluish color. In the case of complete combustion, the products of the reaction are sulfur oxide (4) and water. Given that the furnace gas is an acid oxide, in solution it forms a weak sulfuric acid, which stains the blue litmus paper in red.

In the case of an insufficient amount of hydrogen sulphide, crystalline sulfur is formed. This process is considered to be an industrial method of obtaining pure sulfur from hydrogen sulphide.

This chemical has also been shown to have excellent recovery abilities. They are manifested, for example, in the interaction with salts, halogens. In order to conduct a similar reaction under laboratory conditions, a solution of hydrogen sulfide is poured into chloroform and bromine test tubes, and discoloration is observed. As the reaction product, the formation of crystalline sulfur is observed.

The chemical reaction of hydrogen sulphide with water leads to the formation of the hydroxonium cation H3O +.

Hydrogen sulphide is capable of forming two kinds of compounds: sulfides (middle salts) and hydrosulfides (acid salts).

In alkaline and alkaline-earth metals, sulphides are colorless compounds. In heavy metals (copper, nickel, lead) they are black. Manganese sulphide has a pink color. Many salts do not dissolve in water.

A qualitative reaction to sulphides is the interaction with a solution of copper sulfate (2). The product of this interaction is the precipitation of a black precipitate of copper sulfide (2).

Conclusion

In nature, this substance is found in mineral springs, volcanic gases. This compound is a product of decay of animals and plant organisms, it is distinguished by a characteristic smell of hydrogen sulfide. Natural sulphides are found in the composition of rare metals, in metallurgy from them the corresponding elements are obtained. It is also important to remember that hydrogen sulphide is a powerful poisonous substance.