Page 56 - Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)
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IR-3.2 E L E M E N T S
The IUPAC-approved names of the atoms of atomic n umbers 1-111 for use in the
English language are listed in alphabetical order in Table I*. It is obviously desirable that the
names used in any language resemble these n ames as closely as possible, but it is recognized
that for elements named in the past there are often well-established and very different names
in other l anguages. I n t he footnotes of Table I, certain names are cited which are not used
now in English, but which either provide the basis of the atomic symbol, or the basis of
certain affixes used in nomenclature.
For use in chemical formulae, each atom is represented by a u nique symbol in upright
type as shown i n T able I. In addition, the symbols D a nd T m ay be used for the hydrogen
isotopes o f m ass n umbers two and three, respectively (see Section IR-3.3.2).
IR-3.1.1 Systematic nomenclature and symbols for new elements
Newly discovered elements may be referred to in the scientific literature but until they have
received p ermanent names and symbols from IUPAC, temporary designators are required.
Such elements may be referred to by their atomic n umbers, as in ‘element 120’ for example,
but IUPAC has approved a s ystematic nomenclature and series of three-letter symbols
(see Table II). 2
The name is derived directly from the atomic number of the element using t he following
numerical roots:
0 ¼ nil 3 ¼ tri 6 ¼ hex 9 ¼ enn
1 ¼ un 4 ¼ quad 7 ¼ sept
2 ¼ bi 5 ¼ pent 8 ¼ oct
The roots are put together in the order of the digits which make up the atomic number
and terminated by ‘ium’ to spell out the name. The final ‘n’ of ‘enn’ is elided when i t o ccurs
before ‘nil’, and the final ‘i’ of ‘bi’ and of ‘tri’ when i t o ccurs before ‘ium’.
The symbol for the element is composed of the initial letters of the numerical roots
which make u p t he name.
Example:
1. element 113 ¼ ununtrium, symbol Uut
IR-3.2 I N D I C A T I O N O F M A S S , C H A R G E A N D A T O M I C N U M B E R
U S I N G I N D E X E S ( S U B S C R I P T S A N D S U P E R S C R I P T S )
The mass, charge and atomic n umber of a n uclide are indicated by means of three indexes
(subscripts a nd superscripts) placed around the symbol. The positions are occupied as
follows:
left upper index m ass n umber
left lower index a tomic number
right upper index c harge
n1 n 1n n
A c harge placed on an atom of symbol A i s i ndicated as A or A , n ot as A or A .
* T ables numbered with a R oman numeral are collected together at the end of this book.
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