Dmitri Mendeleev was a wild-haired, long-bearded Russian chemist who reportedly arranged the elements into a periodic table during a marathon card game, sorting element cards the way he sorted playing cards — by suit and number. Whether the card story is myth or reality, his table predicted the existence and properties of elements that had not yet been discovered, and it remains the organizing framework of all chemistry.

This episode traces Mendeleev from his Siberian childhood through his studies in Western Europe, the creation of the periodic table, the predicted elements that vindicated his system, and the personal chaos — including a bigamous marriage — that scandalized Russian society.

• Mendeleev’s Siberian origins and the journey to St. Petersburg that nearly killed his mother
• The card game legend and the systematic arrangement of elements by atomic weight
• The predicted elements — gallium, scandium, germanium — that proved the table was real
• His bigamous marriage, the Nobel Prize he was denied, and his lasting framework for all chemistry