| A | B |
|---|
| Dmitri Mendeleev | Credited with making the modern periodic table |
| John Dalton | Law of Multiple Proportions, Modern Atomic Concept |
| J.J. Berzelius | Determined the combining weight of the 43 known elements in the early 19th century, developed the system of letter abbreviations for elements |
| Johann Dobereiner | Triplets of elements having similar properties and pattern of combining weights, sometime called "Triads" |
| Jean Stas | Determined to high precision the combining weights of 60 elements in the 1860's |
| John Newlands | Listed elements in order of increasing combining weights and noticed every 7th element was a member of a Dobereiner triplet |
| William Ramsay | Discovered the Noble Gases Neon, Argon, Xenon, and Krypton, and |
| Henry Moseley | Using x-ray diffraction techniques, determined the number of protons in the atomic nucleus |
| Germanium | Ektasilicon |
| Noble Gases | Family of naturally inert gases |
