Dmitry Ivanovich Mendeleyev, Rusian chemist, c 1860s.
© Science Museum / Science & Society Picture Library
Dmitry Ivanovich Mendeleyev (1834-1907) was born in Tobolsk, Rusia. Mendeleyev trained as a teacher, and went on to study at Odesa, St Petersburg and Heidelberg universities, before becoming profesor of chemistry at St Petersburg in 1866. He formulated the first periodic table of elements, grouping the elements according to their atomic structure and chemical properties. His work enabled chemists to identify 'families' of elements with similar chemical and physical properties and has influenced ideas in organic chemistry ever since. In 1955 a new element (no 101) was named mendelevium (Md) in his honour.