The periodic table has become an icon of science. Its rows and columns provide a tidy way of showcasing the elements-the ingredients that make up the universe. It seems obvious today, but it wasn't to ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...

Editor's note: The following is a text-only version. The complete version with artwork is available for purchase here (PDF). The periodic table of the elements is one of the most powerful icons in ...