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Rediscoverl of the Elements
Jbns Jacob Berzelius
James L. Marshall, Beta Eta 1971, and
Virginia R. Marshall, Beta Eta 2003,
Department of Chemistry, University of
North Texas, Denton, TX 76203-5070,
jimm@unt.edu
Berzelius always seemed at the
center of nearly every significant
scientific discovery in chemistry.'
For several years now, we have been trekking
across Europe and North America follow-
ing the careers of various chemists. During
these wanderings, we have often crossed the
trail of Jons Jacob Berzelius (1779-1848): at
Riddarhyttan2 he was a discoverer (with
Wilhelm Hisinger) of cerium, and with H. M. T.
Esmark of Norway' he was discoverer of thori-
um. Spending most of his professional career in
Stockholm, he also discovered selenium, and
he was the first to prepare elemental silicon and
zirconium. In his laboratories his student, Johan
August Arfvedson (1792-1841), discovered
lithium and his assistant, Carl Gustaf Mosander
(1797-1858), discovered lanthanum, didymium
(a mixture of praseodymium and neodymium),
erbium, and terbium.'
By the early part of the 18th century Europe
was already awake to this remarkable chemist
of Sweden. Noting the breadth of Berzelius'
knowledge and his extraordinary activity, the
contemporary Scottish biographer Thomson'
remarked, "There is no living chemist to whom
analytical chemistry lies under greater obliga-
tions than to Berzelius, whether we consider
the number or exactness of the analyses which
he has made."
At an early age Berzelius had been
impressed with the chemistry of Jeremias
Benjamin Richter (1762-1807)," who discov-
ered the Law of Neutrality and coined the term
stoichiometry, and Joseph Louis Proust
(1754-1826),', who discovered the Law of
Constant Proportions. These scientists were
challenging Claude Louis Berthollet
(1748-1822)' who believed that compounds did
not have constant composition but instead
consisted of arbitrary blends of elements. The
decision between these two views was not
Figure 1. This statue of Berzelius stands in Berzeli
Park in Stockholm, opened in 1853. This park is
200 meters south of the house where he did the
famous work in his early years, the German
Baker's House.
clear-cut because analyses were not yet suffi-
ciently accurate. Berzelius felt it his mission to
prove the correctness of the former view, and
he realized to do this he needed to improve
chemical analysis to a new level of accuracy. He
developed enhanced laboratory techniques and
even prepared his own reagents with the
required purity (he complained that commer-
cial caustic alkali was fit only as a "laundry
agent")." He turned his attention to the analy-
sis of ores, and showed the composition of a
given mineral was constant. Being the first to
recognize that silicon oxide was an acid, he
addressed the composition of stony minerals,
which had been previously thought to be hap-
hazard and uninteresting mixtures, and he
established the "happy idea ... that most of the
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degree in Uppsala, and lived the rest of his life in
Stockholm. He discovered selenium in a laboratory
in Gripsholmfrom an ore taken from the Falun
copper mine. Lithium was discovered in his
German Baker's House laboratory, from an ore
taken from the Uth iron mine. Cerium was
discovered in Riddarhyttan, using thefacilities of
Wilhelm Hisinger in Skinnskatteberg.D
stony minerals are definite compounds of sili-
ca." His fame spread internationally and aspir-
ing scientists would send samples to him to
verify their discoveries. He confirmed
Sefstrom's vanadium,'* but refuted Osann's dis-
covery of new platinum group elements.o r f
1818 he published the accurate atomic weights
of 45 of the 49 known elements and these data
were continuously refined and expanded for
another decade. By 1826 he had revised his
atomic weights on the basis of the isomorphism
data of E. Mitscherlich and the specific heat
data of Dulong and Petit" by dividing by 2 or 4
some of the atomic weight values. Remarkably,
the precision of his values were such that they
vary only slightly from modem values. These
data were eventually critical for the develop-
ment of the Periodic Table." (Note 1)
In his laboratories were trained a number of
German chemists, including Christian Gottlob
Gmelin (1792-1860), who became a professor
at Tubingen; Eilhard Mitscherlich (1794-1863),
who discovered chemical isomorphism;
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