The Periodic Table of the Elements
Lecture no. 20 from the course: The Joy of Science
Taught by Professor Robert M. Hazen | 31 min | Categories: The Great Courses Plus Online Science Course
Long before Bohr, chemists realized that there are many kinds of atoms—the chemical elements. Elements cannot be broken down into other substances by any ordinary physical or chemical means. In 1869, Dmitri Mendeleev used observed similarities to draw up a periodic table of 63 chemical elements. Subsequent discoveries have lengthened the table but not altered its basic form.