Bohuslav Brauner
Bohuslav Brauner (May 8, 1855 – February 15, 1935) was a
Czech chemist from the
University of Prague, who investigated the properties of the
rare earth elements, especially the determination of their
atomic weights. Brauner predicted the existence of the rare earth element
promethium ten years before the existence of the gap was confirmed experimentally (although the element was still undiscovered). In the 1880s, when he already had started lecturing in Prague, he still competed internationally in cycling races.
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