Selenium acid and telluric acid

Selenium acid and telluric acid

The highest oxidation states of selenium and tellurium corresponding to selenic and telluric acids are obtained by the action of strong oxidants (chloric, chromic) on selenic or telluric acids. They are separated in a free state and are colorless crystalline substances that dissolve easily in water. Selenic acid has two known crystalline hydrates: H2SeO4 * H2O and H2SeO4 * 4H2O.

Pure selenic acid can be obtained by applying sulfuric acid to barium selenate:

BaSeO 4 + H 2 SO 4 = BaSO 4 + H 2 SeO 4.

Concentrated selenic acid is a strong oxidant, which is better than concentrated sulphuric acid (which is how H2SeO4 dissolves not only silver but also gold).

Evaporation tellurium acid solution will generate crystalline hydrate Н teo4 2 * 2 2 О Н. The hydrogen atoms that make up the crystalline hydrate are characterized by their ability to be partially or completely replaced by metals. For example, salt is known as Ag6TeO6, which corresponds to the hexalkali, or so-called orthotelluric acid H6TeO6. Telluric acid, unlike selenic acid, is very weak.

Sulfur dioxide reduces telluric acid to the element tellurium. At the same time, selenic acid was reduced to selenite only by the reductant. It can be used to separate tellurium from selenium.

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9 Rhenium characteristics	10 The discovery history of Rhenium
11 Extraction of selenium from gold bearing stone	12 Selenium is extracted from dust by sulphate and cellulose sulphate plants
13 Selenium and tellurium are extracted from anode slag for copper refining	14 Sources of selenium and tellurium
15 Applications of selenium and tellurium	16 Selenides and tellurides
17 A hydrogen compound of selenium and tellurium	18 Small molecular compound of selenium and tellurium
19 Selenate and telluride	20 Selenium acid and telluric acid