| A | B |
|---|
| Numbr of elements compiled by Lavoisier in 1790 | 23 |
| Number of elemnts compiled by 1870 | 70 |
| Basis of the organization system proposed by John Newland in 1864 | Increasing Atomic Mass |
| Both the chemical and physical properties repeated every eight elements | Newlands "Law of Octaves" |
| Creator of the first periodic table | Dmitri Mendeleev |
| Rearranged according to number of protons | Mosley's Periodic Table |
| Founders of atomic mass and elements properties | Lothar Meyer and Dmitri Mendeleev |
| Repetition of both chemical and physical properties | Periodic Law |
| Nuclear Charge, atomic size or radius, ionization energy, electron affinity, electronegativity, metallic character, reactivity, bonding characteristics, crystal, configurations, acidic properties, densties | Examples of Periodic Trends |
| The s, p, d, and f orbital within a given shell have slightly different energies | Effective Nuclear Charge |
| Unit for effective nuclear charge | Zeff |
| Half the distance between adjacent nucli of the same element | Atomic Radius |
| Half the distance between adjacent nuclei of the same ion | Ionic Radius |
| Ions of different elements that contain the same number of electrons | Isoelectronic Ions |
| The amount of energy necessary to remove the outermost electron from an isolated neutral atom in the gaseous state to infinity | Ionization Energy |
| Energy change that occurs when an electron is added to an isolated atom in the gaseous state | Electron Affinity |
| The reactive ability of an atom to attract electrons in a chemical bond | Electronegativity |
| The ability for an atom to combine with other atoms | Reactivity |
