Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. Additional technical, research and safety (MSDS) information is available as is a Reference Calculator for converting relevant units of measurement. Typical and custom packaging is available. American Elements produces to many standard grades when applicable, including Mil Spec (military grade) ACS, Reagent and Technical Grade Food, Agricultural and Pharmaceutical Grade Optical Grade, USP and EP/BP (European Pharmacopoeia/British Pharmacopoeia) and follows applicable ASTM testing standards. Selenium Metal 78 isotopic material is generally immediately available. For thin film applications it is available as rod, pellets, pieces, granules and sputtering targets and as either an ingot or powder. Selenium Metal is also available in ultra high purity and as nanoparticles. Selenium Metal 78 additionally has special application in bioavailability as an essential nutrient.

Selenium 78 Metal is one of over 250 stable metallic isotopes produced by American Elements for biological and biomedical labeling, as target materials and other applications. It is both naturally occurring and produced by fission. Selenium 78 Metal (Selenium-78) is a stable (non-radioactive) isotope of Selenium. Thin Film Deposition & Evaporation Materials.Additive Manufacturing & 3D Printing Materials.Possible compounds with halogens are SeF 2 and SeCl 2. Because of its electron configuration, you may find selenium bound to two halogens that each offers the selenium atom one electron. Speaking of the number six, selenium is found to have six naturally occurring isotopes. Selenium compounds have been found that have valences of -2, 4, and 6. The six electrons in the outermost shell allow selenium to have a variety of valence numbers. Selenium specifically has an electron configuration of 2-8-18-6. This family has six electrons in the outermost shell.

Selenium is a member of the sulfur family with elements including tellurium and polonium. So remember when you look at our breakdown that the electrons aren't always in a nice neat order as shown here. They are found in clouds that can have different shapes that include spheres and dumbbell-like shapes. As you learn more about atomic structure, you will learn that the electrons don't stay in defined areas around the nucleus. The electrons like to be in separate shells/orbitals. In an atom, the electrons spin around the center, also called the nucleus. Each of those colored balls is an electron.

If you think this is a little over your head, go back and look at the elements 1-18 that have organizations that are a little more simple. Let's take a look at the arrangements of electrons in the basic elements (left and right sides of the table) of period four and the more complex arrangements of the transition elements (in the middle of the row). You may have an easy way to know the number of electrons in a neutral atom, but the placement of those electrons gets a little more complex. Now we're working with the fourth period/row in the table of elements. It tells you the mass of one atom, how many pieces are inside, and where it should be placed on the periodic table. That box on the left has all of the information you need to know about one element.

Selenium electron configuration