The modern periodic table, arranged in rows and columns, was first introduced by Dmitri Mendeleev in 1869. At the time ... As a rare and short-lived element with atomic number 118, Oganesson can only ...

He expounded this idea at the Karlsruhe Congress in Germany in 1860 – the first ever international chemistry conference. Among the many pioneering chemists in attendance was one Dmitri Ivanovich ...