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Secondary School Feature Articles
* Before There Was Chemistry: The Origin of the Elements as
an Introduction to Chemistry, by Neil Glickstein, p 353.
The Heaviest Elements
Hanging on a wall in most chemistry classrooms
is a periodic table that contains a smaller number of entries
than the 112 known elements. Several of the heaviest elements
are likely to be indicated with designations that appear
particularly strange to students, such as Unh for element number
106. The periodic tables printed in textbooks often contain
these designations as well. Changes are expensive for publishers of
wall charts and textbooks, so the lag between discovery or
formal naming is in part a matter of economics. And even when
new element symbols are added, most school instructional
budgets do not permit frequent replacement of expensive wall
charts. The periodic table appearing in this month's
"Viewpoints: Chemists on Chemistry" article by Hoffman and Lee (p
331) contains entries for 112 elements, although no symbols
are given for elements 110-112.
The temporary symbols and names for elements
were established by the International Union of Pure and
Applied Chemistry (IUPAC) in 1979 (1, 2) but they never were
popular with workers in the field. Because the system of
temporary naming does not commonly appear in
textbooks, the four rules for determining the IUPAC-approved
temporary name are repeated below as a convenient resource:
1. The name is derived directly from the atomic number
of the element using the following numerical roots: 0
= nil; 1 = un; 2 = bi; 3 = tri; 4 = quad; 5 = pent; 6 =
hex; 7 = sept; 8 = oct; 9 = enn.
2. The roots are put together in the order of the
digits that make the atomic number and are terminated
by ium to spell out the name. The final
n of enn is elided when it occurs before
nil, and the final i of bi and
of tri when it occurs before ium.
3. The symbol of the element is composed of the
initial letters of the numerical roots that make up the name.
4. The root un is pronounced with a long
u, to rhyme with moon. In the element names each root is to
be pronounced separately.
These rules can be applied to understand the
temporary symbols that still appear on many periodic tables, as
indicated in the table below.
There was a long-running controversy over naming
the elements in the table, but permanent names and symbols
were approved in August 1997 and eventually new textbook editions
and periodic tables will reflect the IUPAC
decision. It is likely that elements 110-112 will receive
official names much more quickly than did elements
104-109. Because experts in the field find it simpler to say
"element 110" than "ununnilium", it is possible that temporary
names will find little use in the future. Nevertheless, it is easy
to follow the rules and arrive at these names: 110,
Ununnilium (Uun); 111, Unununium (Uuu); 112, Ununbium
(Uub); 113, Ununtrium (Uut).
In addition to the article by Hoffman and Lee on
the chemistry of the heaviest elements, this issue contains
four articles related to the discovery of the elements and
nuclear reactions. A Secondary School Chemistry feature
article, authored by a high school teacher (see box), explains how
a study of the origin of the elements can be used as a
theme for introducing chemical and physical concepts to
students. Authors Olbris and Herzeld describe a new game for
learning about nuclear reactions (p 349). The game board can
be downloaded, free of charge, from a Web site.
Previous issues of JCE have carried articles that trace
the progress of discovery of the heaviest elements. Nobel
laureate Glenn T. Seaborg has authored several articles that have
been published in JCE. Three of my favorites are ones in which
he provides historical context and insights into the
development of understanding that made new discoveries possible
(3). The personal recollections of the author make the historical
aspects much more real and interesting than textbook accounts
and provide a lively connection between chemistry and history.
High School Program at the Anaheim ACS Meeting
See page 301 for information about the outstanding
program that will take place March 22 as part of the Division
of Chemical Education Program. This event has been
planned especially for you and I look forward to seeing you
there! While at the meeting be sure and visit the
JCE booth #1051, in the exposition hall.
JCE at the Boston NSTA Meeting
Later in the same week as the ACS
meeting, the NSTA Convention in Boston offers many interesting
sessions and events. Be sure to visit the
JCE booth, #2037, to examine print and electronic media resources you can use in your
classroom. We look forward to meeting and talking with you.
Literature Cited
1. Pure Appl.
Chem. 1979, 51, 38-44.
2. Orna, M. V. J. Chem.
Educ. 1982, 59, 123.
3. Seaborg, G. T. J.
Chem. Educ. 1969, 46, 626-634;
1985, 62, 463-467; 1989,
66, 379-384.
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