Systematic element name

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A systematic element name is the temporary name and symbol assigned to newly synthesized and not yet synthesized chemical elements. In chemistry, a transuranic element receives a permanent name and symbol only after its synthesis has been confirmed. In some cases, this has been a protracted and highly political process (see element naming controversy and Transfermium Wars). In order to discuss such elements without ambiguity, the International Union of Pure and Applied Chemistry (IUPAC) uses a set of rules to assign a temporary systematic name and symbol to each such element. This approach to naming originated in the successful development of regular rules for the naming of organic compounds.

The IUPAC rules[edit]

  digit     root   symbol pronunciation
0 nil n /nɪl/
1 un u /n/
2 b(i) b /b/
3 tr(i) t /tr/
4 quad q /kwɒd/
5 pent p /pɛnt/
6 hex h /hɛks/
7 sept s /sɛpt/
8 oct o /ɒkt/
9 en(n) e /ɛn/
Suffix -ium none /əm/

The temporary names are derived systematically from the element's atomic number. Each digit is translated to a 'numerical root', according to the table to the right. The roots are concatenated, and the name is completed with the ending suffix -ium. Some of the roots are Latin and others are Greek; the reason is to avoid two digits starting with the same letter (Ex: 0 = nil, 9 = enn, 4 = quad, 5 = pent, 6 = hex, 7 = sept) . There are two elision rules designed to prevent odd-looking names.

  • If bi or tri is followed by the ending ium (i.e. the last digit is 2 or 3), the result is '-bium' or -'trium', not '-biium' or '-triium'.
  • If enn is followed by nil (i.e. the sequence -90- occurs), the result is '-ennil-', not '-ennnil-'.

The systematic symbol is formed by taking the first letter of each root, converting the first to a capital.

The suffix -ium overrides traditional chemical suffix rules, thus 117 and 118 are ununseptium and ununoctium, not ununseptine and ununocton.

All elements up to atomic number 112, as well as elements 114 and 116, have received individual permanent names and symbols. So the systematic names and symbols are only used for unnamed elements 113, 115, 117, 118, and higher. The systematic names are exactly those with 3-letter symbols.

Notes[edit]

Element 122 un + bi + b + ium = unbibium (Ubb) (instead of "unbibiium")
Element 167 un + hex + sept + ium = unhexseptium (Uhs) (instead of "unsexseptine")
Element 190 un + en + nil + ium = unennilium (Uen) (instead of "unennnilium", or "unnonanilium")
Note: These examples show conjectured elements.
As of 2014, ununoctium, element 118, is the highest-numbered element discovered.

Examples in Period 8 of the periodic table:

Period 8 in the extended periodic table based on the Aufbau principle
Period 8 119
Uue
120
Ubn
121
Ubu
122
Ubb
123
Ubt
124
Ubq
125
Ubp
126
Ubh
127
Ubs
128
Ubo
129
Ube
130
Utn
131
Utu
132
Utb
133
Utt
134
Utq
135
Utp
136
Uth
137
Uts
138
Uto
139
Ute
140
Uqn
141
Uqu
142
Uqb
143
Uqt
144
Uqq
145
Uqp
146
Uqh
147
Uqs
148
Uqo
149
Uqe
150
Upn
151
Upu
152
Upb
153
Upt
154
Upq
155
Upp
156
Uph
157
Ups
158
Upo
159
Upe
160
Uhn
161
Uhu
162
Uhb
163
Uht
164
Uhq
165
Uhp
166
Uhh
167
Uhs
168
Uho
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External links[edit]