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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