The element possessing 34 electrons is Selenium (Se). The identity of any neutral element is determined by the number of protons in its nucleus, known as the atomic number. Since a neutral atom must have an equal number of protons and electrons, an element with 34 electrons must have an atomic number of 34. This confirms that the element is Selenium.
The Element’s Atomic Identity
The atomic number for Selenium is 34, which matches the count of 34 electrons in its neutral state. This places the element in Group 16 of the periodic table, often called the Chalcogens, and in the fourth period. Its position connects it chemically to elements like sulfur and tellurium, sharing similar outer shell electron arrangements. The 34 electrons are arranged in a shell structure of 2, 8, 18, and 6. This configuration means the outermost shell contains six valence electrons, which dictates how Selenium interacts with other elements.
Key Chemical and Physical Characteristics
Selenium is classified as a metalloid, exhibiting properties between those of metals and nonmetals. At room temperature, it exists as a solid and can form several distinct structures called allotropes. One stable form is a dense, metallic-looking gray solid.
Photoconductivity and Industrial Use
This gray form is notable for its photoconductivity, where its electrical conductivity increases significantly when exposed to light. This characteristic is applied in electronic components, such as photocopiers and solar cells. Industrially, Selenium is used in glass manufacturing to remove the greenish tint caused by iron impurities or to impart a deep red color.
Biological Roles and Essential Functions
Selenium is an essential trace mineral for human health, required by the body in small amounts for proper functioning. Its biological importance stems from its incorporation into selenoproteins. Selenocysteine is the form in which Selenium is incorporated into the active site of these proteins. Many selenoproteins, such as glutathione peroxidases, function as powerful antioxidants. These enzymes protect cells from damage by neutralizing reactive oxygen species and free radicals.
Intake and Toxicity
Selenium also plays a role in regulating thyroid hormone metabolism and supporting immune function. The element has a narrow therapeutic window, demonstrating a fine line between required intake and toxicity. Deficiency can lead to impaired immune response and is linked to conditions like Keshan disease. Conversely, excessive intake can cause selenosis, characterized by symptoms like hair loss, skin lesions, and nerve damage. Common dietary sources include Brazil nuts, seafood, and various meats.