Which society heard Mendeleev's formal periodic-law presentation on 6 March 1869?

The Russian Chemical Society heard Dmitri Mendeleev’s formal periodic-law presentation on 6 March 1869.

Mendeleev’s paper was titled “The Dependence between the Properties of the Atomic Weights of the Elements.” It arranged elements by atomic weight while grouping those with recurring chemical properties and related valences. The presentation marked a decisive step toward the modern periodic table.

The meeting took place in Saint Petersburg. Mendeleev did not personally deliver the paper; because he was ill, the society’s secretary, Nikolai Menshutkin, presented it on his behalf. Mendeleev soon published the work in Russian and circulated copies internationally.

A common mix-up is confusing this event with later recognition of the periodic table. German chemist Lothar Meyer independently developed a similar classification, while English chemist John Newlands had earlier proposed the Law of Octaves. Mendeleev’s system stood out for leaving gaps and predicting undiscovered elements.