The latest release of the Periodic Table (dated 4 May 2022) includes the most recent abridged standard atomic weight values released by the IUPAC Commission on Isotopic Abundances and Atomic Weights (), compiled as part of the 2021 Table of Standard Atomic Weights 2021.For elements that lack isotopes with a characteristic isotopic abundance in natural terrestrial …

1 H hydrogen 1.0080 ± 0.0002 1 18 3 Li lithium 6.94 ± 0.06 4 Be beryllium 9.0122 ± 0.0001 11 Na sodium 22.990 ± 0.001 12 Mg magnesium 24.305 ± 0.002 19 K potassium 39.098

1 H hydrogen 1.008 [1.0078, 1.0082] 1 18 3 Li lithium 6.94 [6.938, 6.997] 4 Be beryllium 9.0122 11 Na sodium 22.990 12 Mg magnesium 24.305 [24.304, 24.307] 19 K potassium

IUPAC serves the international scientific endeavor in the dual function of a basic science and a mission-oriented Union. The Union is in a unique position

The International Union of Pure and Applied Chemistry (IUPAC) The International Union of Pure and Applied Chemistry (IUPAC) is the world authority on digital standards in chemistry; chemical nomenclature and terminology, including the naming of new elements in the periodic table; on standardized methods for measurement; and on atomic weights. Founded in 1919, IUPAC has …

This website provides kinetic and photochemical evaluated data in the form of summary tables of kinetic data and individual sheets of reaction data, e.g. for some heterogeneous reactions, a number of halogen, Ox, HOx, NOx and SOx photolysis reactions, and a number of gas-phase Ox, HOx, NOx, SOx and organic reactions.

2016年8月17日 · www.ISOTOPESMATTER.com brings free engaging and interactive learning resources to the fingertips of students and educators around the world.

The scientific work of IUPAC is conducted largely through a formal Project system in which proposals from chemists around the world are peer-reviewed.

2022年5月17日 · From global chemists’ need for standardization and the vision to unite.

Each year IUPAC endorses a large number of independently organized conferences, symposiums and workshops that cover a wide range of specialized topics in chemistry.