Peter Jacob Hjelm

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Peter Jacob Hjelm (born October 2, 1746 in Sunnerbo Härad , Småland , † October 7, 1813 in Stockholm ) was a Swedish chemist and mineralogist.

Life

Hjelm, whose father was a pastor, began studying chemistry at Uppsala University in 1763 and received his doctorate there . In 1774 he was appointed to the Stockholm Bergskollegium as an auscultant (a post similar to an auscultator in the judiciary, but who also taught) . From 1782 he was a tester (metallurgist) of the royal Swedish mint. Two years later he became a member of the Swedish Academy of Sciences . In 1794 he took over the management of the Stockholm Mint and became head of the chemical laboratory of the Bergskollegium.

In 1781 he succeeded in discovering the element molybdenum when, on behalf of Carl Wilhelm Scheele, he carried out chemical investigations on the mineral molybdenite (molybdenum sulfide, then called molybdenum and, like graphite, also called water lead). Scheele had already demonstrated the difference to graphite and Bengt Qvist that it contained sulfur. Reactions with nitric acid gave a white salt, and Torbern Bergman suggested to Scheele that it was an oxide of a new metal. Since Scheele lacked a suitable stove, he transferred the reduction to Hjelm, with whom he was friends and whom he probably already knew in Uppsala.

He also studied manganese, discovered by Johan Gottlieb Gahn in 1774 .

He also worked as a geologist, for example he described the porphyry in Dalarna .

literature

Web links

Wikisource: Peter Jacob Hjelm  - Sources and full texts

Individual evidence

  1. ^ Mary Elvira Weeks, Discovery of the Elements, Verlag des Journal of Chemical Education 1956, pp. 261f
personal data
SURNAME Hjelm, Peter Jacob
BRIEF DESCRIPTION Swedish chemist and mineralogist
DATE OF BIRTH October 2, 1746
PLACE OF BIRTH Sunnerbo Härad
DATE OF DEATH October 7, 1813
Place of death Stockholm