Converters & Calculators
Selenium: Element Properties And Uses
Description
Selenium is an essential trace element with distinct chemical behaviour and physical properties. It is employed globally in industry, medicine and electronics.
Introduction
Selenium, primarily found in mineral deposits, is essential in trace amounts for living organisms and is utilised in a wide range of industrial products. Its capacity to form compounds with various oxidation states renders it versatile in chemical reactions and manufacturing processes. Researchers and engineers have long investigated selenium because its chemical characteristics allow integration into devices such as photovoltaic cells and electronic circuits.
Description of Chemical Properties
Selenium’s chemical behaviour is noteworthy because of its variable oxidation states, typically ranging from -2 to +6. This range enables the formation of a variety of compounds with other elements. In chemical reactions, selenium participates in redox processes, and its compounds are frequently examined for their semiconductor properties and catalytic activity. The element’s electron configuration contributes to its reactivity among nonmetals and facilitates the synthesis of organic and inorganic compounds.
In laboratories, selenium compounds are often employed in experiments on photocatalysis and corrosion inhibition, thereby underlining its relevance in modern chemical industry.
Physical Properties
Physically, selenium exhibits either metallic or nonmetallic properties depending on its allotrope. The element occurs in forms such as amorphous and crystalline variants, each displaying distinct colours and textures. Some selenium allotropes display a metallic grey appearance, while others exhibit a red hue. These differences are important when selecting the appropriate form for specific industrial applications.
|
Property |
Value |
Notes |
|
Atomic Number |
34 |
Standard element number |
|
Atomic Weight |
~78.96 |
Based on the natural isotopic composition |
|
Density |
4.81 g/cm³ |
Measured in the solid state |
|
Melting Point |
220 °C |
Varies for different allotropes |
|
Boiling Point |
685 °C |
Typical value for the crystalline form |
|
Appearance |
Metallic grey to red |
Dependent on the allotrope |
Further information is available at Stanford Advanced Materials (SAM).
Common Uses
Selenium is employed in a range of applications that benefit from its specific properties.
In the field of electronics, it is utilised for its photoelectric sensitivity in photocopiers and photovoltaic cells.
In the glass industry, selenium is applied to remove any green tint from glass and may be added to achieve a reddish colour if required.
Additionally, selenium is incorporated into dietary supplements as an essential micronutrient to support metabolic functions and the immune system. Its compounds are used in pigments for ceramics and plastics, as well as in lubricants to enhance machinery performance.
Preparation Methods
The methods for preparing selenium are carefully designed to ensure both its purity and effectiveness across various applications.
Typically, selenium is recovered as a by-product during the refining of ores, for example, copper. In the extraction process, the ore is generally roasted to convert selenium into a volatile compound, which is then condensed and purified. Alternative processing methods may involve chemical reduction procedures to obtain elemental selenium.
These processes have been optimised to limit contamination and maintain selenium’s chemical and physical properties. Detailed procedures and technological developments have refined these methods, thereby making selenium widely available for laboratory research and industrial production.
Frequently Asked Questions
What is selenium?
Selenium is a non-metal element that is essential in trace amounts for biological functions and is employed in various industrial applications.
How is selenium typically produced?
It is commonly extracted from selenide ores during metal refining processes, such as copper, through roasting and purification procedures.
How is selenium commonly used?
It is utilised in photovoltaic cells, photocopiers, glass production, pigments and as an important micronutrient in dietary supplements.
What impact do its chemical properties have on its applications?
Its ability to exhibit multiple oxidation states enables the formation of a range of compounds, thereby making it valuable for semiconductors and catalytic processes.
In which industrial products is selenium employed?
High-performance alloys, electronic circuits, specialised pigments and glass products benefit from selenium’s properties.
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