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Download as PDF; Printable version; ... Iron 26 Fe 55.845: Cobalt 27 Co ... This periodic table is the prime form presented at this English wikipedia.
This is a list of chemical elements and their atomic properties, ordered by atomic number (Z).. Since valence electrons are not clearly defined for the d-block and f-block elements, there not being a clear point at which further ionisation becomes unprofitable, a purely formal definition as number of electrons in the outermost shell has been used.
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
Each distinct atomic number therefore corresponds to a class of atom: these classes are called the chemical elements. [5] The chemical elements are what the periodic table classifies and organizes. Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on.
1. Hydrogen 1 H 1.0080: Helium 2 He 4.0026: 2: Lithium 3 Li 6.94: Beryllium 4 Be 9.0122: Boron 5 B 10.81: Carbon 6 C 12.011: Nitrogen 7 N 14.007: Oxygen 8 O 15.999: Fluorine 9 F 18.998: Neon 10 Ne 20.180: 3: Sodium 11 Na 22.990: Magnesium 12 Mg 24.305: Aluminium 13 Al 26.982: Silicon 14 Si 28.085: Phosphorus 15 P 30.974 ...
Of these stable isotopes, only 57 Fe has a nuclear spin (− 1 ⁄ 2). The nuclide 54 Fe theoretically can undergo double electron capture to 54 Cr, but the process has never been observed and only a lower limit on the half-life of 4.4×10 20 years has been established. [22] 60 Fe is an extinct radionuclide of long half-life (2.6 million years ...
In many cases, multiple configurations are within a small range of energies and the small irregularities that arise in the d- and f-blocks are quite irrelevant chemically. [1] The construction of the periodic table ignores these irregularities and is based on ideal electron configurations.
Boca Raton, Florida, 2003; Section 1, Basic Constants, Units, and Conversion Factors; Electron Configuration of Neutral Atoms in the Ground State. (elements 1–104) Also subsection Periodic Table of the Elements, (elements 1–103) based on: G. J. Leigh, Editor, Nomenclature of Inorganic Chemistry, Blackwell Scientific Publications, Oxford, 1990.