Émile Henriot

Émile Henriot ( , ; 2 July 1885 – 1 February 1961) was a French chemist notable for being the first to show definitively that potassium and rubidium are naturally radioactive.

He investigated methods to generate extremely high angular velocities, and found that suitably placed air-jets can be used to spin tops at very high speeds—this technique was later used to construct ultracentrifuges.

He was a pioneer in the study of the electron microscope. He also studied birefringence and molecular vibrations.

He obtained his DSc in physics in 1912 the Sorbonne, Paris, under Marie Curie.

As a professor at the Free University of Brussels he attended the Solvay Conferences of 1924, 1927, 1930, 1933, 1948, 1951 and 1954. For many of the conferences he assisted with preparing the venue or other administrative tasks.