Sources of Selenium uses and production & properties or extract

Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal with properties intermediate between those of a metal and a nonmetal. Selenium is found in small quantities in many minerals, including selenite, selenium sulfide, and selenates.

Sources of Selenium:

1. Copper Ores: Selenium is often found in copper ores and is extracted as a trace element during the refining of copper.

2. Soils: Selenium is present in soil, and plants absorb it and concentrate it in their tissues. Some plants, such as legumes, are particularly good at concentrating selenium.

3. Coal: Selenium is also found in coal and can be extracted as a byproduct of coal combustion.

Uses of Selenium:

1. Solar Cells: Selenium is used in the production of photovoltaic cells, which are used to convert sunlight into electricity.

2. Glass Production: Selenium is used to produce red and brown colored glasses.

3. Alloys: Selenium is used in alloys with other metals, such as stainless steel, to improve their properties.

4. Electronics: Selenium is used in the production of rectifiers, which are used to convert alternating current (AC) to direct current (DC).

5. Nutrition: Selenium is an essential trace element for human nutrition and is required for the proper functioning of the thyroid gland.

Production of Selenium:

1. Roasting: Selenium is produced by roasting selenite or selenium sulfide, which releases selenium as a gas. The gas is then condensed and solidified to produce elemental selenium.

2. Electrowinning: Another method for producing selenium is by electrowinning, where a solution of selenium sulfate is electrolysed to produce elemental selenium.

Properties of Selenium:

1. Physical Properties: Selenium is a red-brown nonmetal that is brittle and has a low melting and boiling point.

2. Chemical Properties: Selenium is a reactive element that forms a number of compounds with other elements. It is also toxic to humans and animals in high doses.

3. Extract: Elemental selenium is extracted from ores using methods such as roasting and electrowinning. Selenium compounds are obtained by chemical reactions with other elements.