On This Day In Chemistry

April 30th

Sir Joseph J. Thomson announced the discovery of the electron on this day in 1897

Thomson was studying the properties of cathode rays, and found that they were over 1,000 times lighter than the hydrogen (H) atom and that they were the same mass irrespective of the parent atom. He called these particles “corpuscules”, but scientists later dubbed them “electrons”.

Related Resources

Day In Chemistry