In this week’s Chemical & Engineering News, the American Chemical Society marks the 150th anniversary of the world’s first scientific conference — yes, a chemistry conference — held Sept. 3, 1860, in Karlsruhe, Germany.
August Kekulé
Atomic scientist,
conference organizer
Friedrich August Kekulé
von Stradonitz
The guy who gets the credit
August Kekulé suggested idea of holding a conference, and he drew support from other chemists frustrated by ongoing quarrels about the relative masses of the constituents of the chemical elements, and hence about the atomic composition of molecules:
Although most chemists believed in atoms and molecules, nobody could agree on molecular formulas. Even simple molecules such as water were hotly debated: Most leading chemists at the time claimed that water’s molecular formula was OH, and a minority argued that it was H2O.
After non-PowerPoint presentations and what weren’t called “breakout sessions” and “breakout group reports”, the participants had agreed to nothing.
Nonetheless, two participants — Lothar Meyer and Dmitri Mendeleev — gained the insights that led them to puzzle out what we call the “Periodic Table of the Elements”, including Mendeleev’s essentially correct assignment of relative masses to the atoms of the elements.
This work meshed with the growing understanding by chemists of the chirality of crystals and of the specific numbers of chemically distinct members of classes of molecules of identical atomic composition. All this (and more) was explained in terms of regularities in inter-atomic bonding and the three-dimensional arrangement of atoms in organic molecules. This atom-based theoretical understanding solved puzzles and made predictions. It was detailed and essentially correct.
Nonetheless, it is often said that it was Albert Einstein, decades later, who established that these atoms really exist. As I’ve said, the implied standard of evidence strikes me as being somewhere between unreasonable and perverse:
“Chemists deserve more credit: Atoms, Einstein, and the Matthew Effect”
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