STN

Names of Trans-Fermium Elements 101-110

The American Chemical Society has adopted the following names for elements 101 to 110 for its primary and secondary publications. These names were adopted by IUPAC and endorsed by the ACS Committee on Nomenclature. The new names differ in only two cases from the names supported by the ACS Committee on Nomenclature and adopted by the ACS publications in 1995. Since 9/97, Dubnium replaced Hahnium for element 105 and Bohrium replaced Nielsbohrium for element 107.


Element New Name Symbol Previous CA Name CAS Reg No
~~~~~~~ ~~~~~~~~~~~~~~~ ~~~~~~ ~~~~~~~~~~~~~~~~ ~~~~~~~~~~
101 Mendelevium Md Mendelevium 7440-11-1
102 Nobelium No Nobelium 10028-14-5
103 Lawrencium Lr Lawrencium 22537-19-5
104 Rutherfordium Rf Rutherfordium 53850-36-5
=> 105 Dubnium Db Hahnium 53850-35-4
106 Seaborgium Sg Seaborgium 54038-81-2
=> 107 Bohrium Bh Nielsbohrium 54037-14-8
108 Hassium Hs Hassium 54037-57-9
109 Meitnerium Mt Meitnerium 54038-01-6
110 Darmstadtium Ds Ununnilium 54083-77-1

The CAS REGISTRYSM nomenclature records for these two elements (and their isotopic and compound forms) are being updated to reflect the new names. Appropriate cross-references from the previous index names and synonyms will guide the users of the printed index. The previous names will also remain as synonyms in CAS REGISTRY.

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