Dmitri Mendeleev

Dmitri Ivanovich Mendeleev was born on 8 February 1834 in Tobolsk, in the Siberian region of the Russian Empire. He was the youngest of a large family. After his father lost his sight and died when Mendeleev was still young, his mother worked to support the family and eventually moved to Saint Petersburg so that Dmitri could pursue higher education.

Mendeleev studied at the Main Pedagogical Institute in Saint Petersburg, then at the University of Heidelberg, before returning to Russia to teach at the University of Saint Petersburg. While writing a textbook on chemistry, he found it necessary to develop a systematic method for organising the known elements.

In 1869, Mendeleev presented his periodic table to the Russian Chemical Society, arranging the 63 then-known elements in order of atomic weight and in groups reflecting similar chemical properties. A notable feature of the table was that he left gaps for elements that had not yet been identified, and he provided predictions about the properties of these missing elements. The subsequent discovery of gallium, scandium, and germanium, whose properties closely matched his predictions, was seen as strong confirmation of his system.

Beyond the periodic table, Mendeleev made contributions to other areas, including research on the properties of gases and liquids and studies of the petroleum industry. He also worked in areas of economic and industrial policy in Russia.

Mendeleev was passed over for the Nobel Prize in Chemistry in 1906, with the award going instead to Henri Moissan. The reasons for this decision have been a subject of historical discussion. He died on 2 February 1907 in Saint Petersburg. Element 101, discovered in 1955, was named mendelevium in his honour.