The Department of Chemistry and the Library of FCT NOVA
proudly associate with the celebrations of the International Year of the Periodic Table

2019 - International Year of the
Periodic Table of Chemical Elements

150^th anniversary of its creation by Russian scientist Dmitri Mendeleiev

"Before the promulgation of the periodic law, the chemical elements were mere fragmentary incidental facts in nature; there was no special reason to expect the discovery of new elements, and the new ones which were discovered from time to time appeared to be possessed of quite novel properties. The law of periodicity first enabled us to perceive undiscovered elements at a distance which formerly were inaccessible to chemical vision, and long ere they were discovered new elements appeared before our eyes possessed of a number of well-defined properties."
[Dmitri Mendeleiev in Faraday Lecture, delivered before the Fellows of the Chemical Society in the Theatre of the Royal Institution, 4 Jun 1889]

1869 is considered as the year of discovery of the Periodic System by the Russian chemist Dimitri Mendeleiev. With 2019 marking the 150^th anniversary of the Periodic Table of Chemical Elements, the United Nations Educational, Scientific and Cultural Organization (UNESCO) has designated 2019 the International Year of the Periodic Table of Chemical Elements (IYPT).

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[Text and images from IUPAC and UNESCO.]