This program chronicles the historical development of the concept of an "element" from the ideas of ancient Greece through modern quantum theory. Viewers learn that as a scientists like Boyle, Dalton and Lavoisier begin to recognize patterns in the behavior of chemicals, they sought a unifying principle that would explain why different elements had different properties. See how Mendeleev sorted through a mountain of data, looking for a logical organization, and learn how he was able to predict the properties of elements years before they were even discovered!

Teacher's guide available under Additional info tag. Optional English and Spanish language tracks.