Hydrobromic acid. Methods of preparation, physical and chemical properties

Hydrobromic acid (also called hydrobromide) is an inorganic hydrogen (H) compound with bromine (Br). It is a colorless gas that forms a dense fog in moist air.

What are the ways of producing hydrogen bromide

Due to the high degree of oxidation of bromic acid, it can not be obtained by the action of sulfuric acid concentrated on metal bromides alkaline. The following reaction occurs:

2KBr (potassium bromide) + 2H2SO4 (sulfuric acid) = K2SO4 (potassium sulphate) + SO2 (sulfur oxide) + Br2 (bromine molecule) + 2H2O (water)

1. In the industry, the production of acids, such as hydrobromic acid, is carried out through a reaction in which the constituent elements interact. For example, the substance we are considering can be obtained by the following method:

H2 (hydrogen molecule) + Br2 (bromine molecule) = 2HBr (hydrobromic acid)

This reaction is feasible at a temperature of 200 to 400 degrees.

2. It is also possible to produce hydrobromic acid in laboratory conditions in several ways.

- by hydrolysis of phosphorus pentabromide or tribromide:

PBr3 (tribromide) + 3H2O (three water molecules) = H3PO3 (phosphoric acid) + 3HBr (hydrobromic acid, chemical formula)
PBr5 (pentabromide) + 4H2O (four water molecules) = H3PO4 (phosphoric acid) + 5HBr (hydrobromide)

- by reduction of bromine:

3Br2 (three bromine molecules) + S (sulfur) + 4H2O (water) = (reaction possible at a temperature of 100-150 degrees) H2SO4 (sulfuric acid) + 6HBr (hydrobromide)
3Br2 (three bromine molecules) + KNO2 (potassium nitrite) + 4H2O (water) = KNO3 (potassium nitrate) + 2HBr (hydrobromide)

- by displacing dilute acid with alkali metals from bromides:

KBr (potassium bromide) + H2SO4 (sulfuric acid) = KHSO4 (potassium hydrogen sulfate) + HBr (released as gas)

3. As a by-product, hydrogen bromide can be obtained by the synthesis of organic bromo derivatives.

Physical properties of hydrobromide:

1. Hydrobromic acid is a gas without color, which has an unpleasant and sharp odor. Strongly smokes in the air. Has high resistance to temperatures.

2. It is highly soluble in H2O (water) and ethanol with formation of electrolyte. An aqueous solution of hydrobromide forms an azeotropic mixture that boils at a temperature of 124 degrees. One liter of water dissolves about half a liter of hydrogen bromide (at 0 degrees).

3. During cooling of the aqueous solution of hydrogen bromide, the following crystal hydrates can be obtained: HBr * H2O, HBr * 2H2O, HBr * 4H2O.

4. Pure hydrobromic hydrogen forms crystals of the orthogoric, space group F mmm.

5. At a temperature of -66.8 degrees it becomes liquid and at 87 degrees it hardens.

Chemical properties of hydrobromide:

1. Hydrobromic acid reacts with water to form a strong monobasic acid . This reaction looks like this:

HBr + H2O (water) = Br- (anion of bromine) + H3O + (hydronium ion)

2. This substance is resistant to high temperatures, however, at 1000 degrees, about 0.5% of all molecules decompose:

2HBr (hydrobromic acid) = H2 (hydrogen molecule) + Br2 (bromine molecule)

3. The chemical compound we are considering reacts with various metals, as well as their bases and oxides. Examples of reactions:

2HBr + Mg (magnesium) = MgBr2 (magnesium bromide) + H2 (released as a gas)
2HBr + CaO (calcium oxide) = CaBr2 (calcium bromide) + H2O (water)
HBr + NaOH (sodium hydroxide) = NaBr (sodium bromide) + H2O (water)

4. Hydrogen bromide is also a reducing agent. It oxidizes slowly in the air. For this reason, its aqueous solutions after a while are painted brown. The reaction will be as follows:

4HBr (hydrobromic acid) + O2 (oxygen molecule) = 2Br2 (bromine molecule) + 2H2O (water)

Application

Bromine hydrogen is used to create (synthesize) various organic derivatives of bromine and to prepare bromides of various metals. Of particular importance is silver bromide, since it is used in the production of film photomaterials.

How is transportation carried out?

In cylinders with a capacity of 68 or 6.8 liters under a pressure of 24 atmospheres.