Heroines of the Periodic Table (Video) (IMAGE) American Chemical Society Caption In 1871, Dimitri Mendeleev's periodic table was presented to the world, but missing many of the 118 elements leaving place-holders for those yet to be discovered. Each element added has a unique story of scientific discovery and we wish to honor women's history month in the international year of the periodic table. This week on Reactions, we wanted to share the story of two of chemistry's most brilliant and bold women and their paths of elemental discovery -- because what they brought to the table changed the world as we know it: https://youtu.be/Zv8jECGdZAY. Credit The American Chemical Society Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.