The discovery of new elements continued after Mendeleyev announced his periodic table of elements (see 1869). In 1874 the French chemist Paul-Emile Lecoq de Boisbaudran (1838-1912) found a zinc ore that displayed hitherto unknown spectral lines. He extracted the new element and named it gallium, from the old Latin word for the area that became France after the fall of the Roman Empire.
Once the discovery was announced, Mendeleyev pointed out at once that the element was his eka-aluminum. He was right. The characteristics and properties possessed by gallium were exactly what he had predicted for eka-aluminum. The validity of the periodic table could not thereafter be denied.
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|Publication:||Asimov's Chronology of Science & Discovery, Updated ed.|
|Article Type:||Reference Source|
|Date:||Jan 1, 1994|
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