Perchloric acid - properties, production, application.

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perchloric acid (formula HClO4) - is a monobasic acid anhydrous.Contains chlorine (Cl) in the higher oxidation state, for this reason, it is a strong oxidizer.EXPLOSION.

Properties perchloric acid

1. It is volatile liquid without color, a lot of smoke in the air, the monomer vapor.Unstable and very reactionary.To this acid characterized avtodegidratatsiya:

3HClO4 = H3O + (cation) ClO- + (anion) + Cl2O7 (chlorine monoxide)

2. This substance is readily soluble in chlorinated and organofluorine solvents such as CH2Cl2 (methylene chloride), CHCl3(chloroform), and others.It can be mixed with other solvents exhibits reducing properties, and rough handling can cause an explosion or fire.

3. It blends well with water (H2O) in any proportion.It forms several hydrates.Concentrated solutions of these acids have slightly oily texture.Aqueous solutions of the acids have a good stability and a low oxidizing ability.Since we are considering the substance with water forms an azeotrope, which is at a temperature of 203 degrees is boiling and contains 72 percent of HClO4.

4. Perchloric acid (Formula HClO4) is one of the strongest acids.Because of this, in its acidic environment some compounds behave like bases.

5. under reduced pressure with gentle heating a mixture of perchloric acid with phosphorus pentoxide formed an oily, colorless liquid - chlorine dioxide:

2HClO4 (perchloric acid) + P4O10 (phosphoric anhydride) = Cl2O7 (chlorine dioxide) + H2P4O11

Methodsobtaining

1. Aqueous solutions of the substance can be obtained in two ways.The first is the electrochemical oxidation of chlorine or hydrochloric acid in concentrated hydrochloric acid, and the second - in the double decomposition of sodium perchlorate or potassium inorganic strong acids.

2. anhydrous perchloric acid can be obtained in two ways, too.The first consists in reacting potassium perchlorate (K) or sodium (Na) with sulfuric acid in concentrated form, and the second - working oleum with an aqueous solution of perchloric acid:

KClO4 (aqueous solution of perchloric acid) + H2SO4 (sulfuric acid) = KHSO4(potassium sulfate) + HClO4 (perchloric acid)

Application perchloric acid

- concentrated solutions are widely used for perchlorates (salts of this acid) in analytical chemistry;

- perchloric acid is used in the decomposition of ores as a catalyst and in the analysis of minerals;

- potassium perchlorate (Formula: KClO4), a salt of this acid, is used to create explosives and magnesium perchlorate (anhydrone, Mg (ClO4) 2) is used as a desiccant.

Safety at work

perchloric acid anhydrous can not long stored and transported as under standard conditions it is rapidly degraded and may eventually spontaneously explode.

Other inorganic chlorine acid:

1. Hydrochloric acid (Formula: HCl) - a strong monobasic acid, caustic, fuming liquid air.Applied electroforming (pickling, etching) and in the hydrometallurgical treatment of metal with tinning or solder, to produce manganese chloride, zinc, iron and other metals.In the food industry the substance is registered as a food additive E507.

2. hypochlorous acid (formula: HClO) - is very weak monobasic acid.May exist only in solutions.Used for sanitary purposes and for bleaching textiles and pulp.

3. chlorous acid (HClO2) - monobasic acid of medium strength.Is unstable in free form, in dilute aqueous solution is usually rapidly degraded.The acid anhydride is still unknown.

4. chloric acid (HClO3) - monobasic strong acid.Do not get in free form, as breaks in concentrated solutions.In aqueous solutions, there is a concentration lower than 30 percent.Quite stable at low temperatures.