Dmitri Mendeleev

Dmitri Mendeleev was a Russian chemist who formulated the periodic law and in 1869 published a periodic table of the elements. What set his version apart was its boldness: he left gaps for elements not yet discovered, predicted their properties, and corrected the accepted values for some known ones. Born in Siberia and based for most of his life in Saint Petersburg, he was also a government adviser on industry, trade and measurement in the late Russian Empire.

Mendeleev was born on 8 February 1834 (27 January in the Old Style calendar then used in Russia) at Verkhnie Aremzyani, a village near Tobolsk. He was the youngest of a very large family. His father, a schoolteacher, went blind and lost his post, and his mother restarted her family's glass factory to support the household. After his father's death and a fire that destroyed the factory, Mendeleev attended the Tobolsk gymnasium.

In 1849 his mother took him across Russia in search of a university place. Moscow turned him away, so they went on to Saint Petersburg, where in 1850 he entered the Main Pedagogical Institute. After graduating he fell ill with tuberculosis and in 1855 moved to Crimea, teaching science at a gymnasium in Simferopol, before returning to the capital, recovered, in 1857.

From 1859 to 1861 Mendeleev worked in Heidelberg on the capillarity of liquids and on the spectroscope. Back in Russia he published a textbook, Organic Chemistry, which won the Demidov Prize. In 1864 he took a professorship at the Saint Petersburg Technological Institute, and in 1865 one at Saint Petersburg University, the year he earned his doctorate with a dissertation on combinations of water with alcohol. In 1868 he helped found the Russian Chemical Society.

About 56 elements were known in the 1860s, and others, including John Newlands and Lothar Meyer, had noticed patterns among them. While writing his textbook Principles of Chemistry, which appeared in two volumes from 1868 to 1870, Mendeleev arranged the elements by atomic weight and found that their chemical properties recurred at regular intervals. He presented his system to the Russian Chemical Society on 6 March 1869. Meyer published a very similar table a few months later.

Mendeleev went further than his rivals. He predicted three missing elements, which he called eka-aluminium, eka-boron and eka-silicon, and described their expected properties. They were identified as gallium, scandium and germanium; gallium was found in 1875 and germanium in 1886. He also argued that the atomic weight of uranium should be roughly doubled, to about 240, close to the modern value.

In 1882 Mendeleev married Anna Popova, a month before his divorce from his first wife was finalised. The Orthodox Church required a seven-year wait before remarriage, and the controversy helped deny him a seat in the Russian Academy of Sciences, international fame notwithstanding.

He resigned from the university in 1890 after clashing with the Ministry of Education about how students were treated. From the 1870s he wrote widely on Russian industry and agriculture, studied the oil industry and helped found Russia's first oil refinery. From 1893 until his death he directed the Bureau of Weights and Measures, where he worked to introduce the metric system to Russia.

Mendeleev was nominated for the Nobel Prize in Chemistry in 1905, 1906 and 1907. In 1906 the prize committee recommended him, but the full academy chose Henri Moissan by a single vote, partly owing to the opposition of Svante Arrhenius. He died of influenza in Saint Petersburg on 2 February 1907 (20 January Old Style), aged 72. Element 101, mendelevium, and a crater on the far side of the Moon bear his name, and he is often called the father of the periodic table.

Mendeleev spent his whole career in the Russian Empire. Our 1878 map shows the empire stretching from Saint Petersburg to Siberia in the decade after his periodic table appeared, and the 1900 map shows it in his final years.