Ernst Gottfried Fischer

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Ernst Gottfried Fischer (July 17, 1754 – January 27, 1831) was a German chemist. He was born in Hoheneiche near Saalfeld. After studying theology and mathematics at the University of Halle, he was a teacher in Berlin before becoming Professor of Physics in 1810. He translated Claude Berthollet's publication Recherches sur les lois de l'affinitié in 1802. He proposed a system of equivalents based on sulfuric acid equal to one hundred.

Stoichiometry contribution[edit]

Jeremias Benjamin Richter's work had little impact until 1802, when it was summarized by Fischer in terms of tables, such as the one below.

According to this table, it takes 615 parts by weight of magnesia to neutralize either 1000 parts by weight of sulfuric acid or 1405 parts by weight of nitric acid. In the early literature on the subject, these weights were referred to as combining weights.

Weights of acids and bases that are chemically equivalent
Bases Acids
Name Parts required to titrate Name Parts required to titrate
Alumina (aluminium oxide) 525 Carbonic acid 577
Magnesia 615 Muriatic acid (hydrochloric acid) 712
Lime (calcium carbonate) 793 Phosphoric acid 979
Calcium hydroxide 793 Oxalic acid 755
Soda (sodium carbonate) 859 Sulphuric acid 1000
Potash (potassium carbonate) 1605 Aqua fortis (nitric acid) 1405
Barite (barium sulfate) 2222 Acetic acid 1480

References[edit]