CHEM 101 Lecture Notes - Lecture 7: Electron Affinity, Metal, Atomic Number
Document Summary
Mendeleev and meyer independently came to the conclusion about how the elements should be grouped, Mendeleev is given more credit because he used his arrangement to correctly predict the discovery of germanium. Effective nuclear charge-electrons are both attracted to the nucleus and repelled by other electrons. The nuclear charge than an electron experiences depends on both factors. Z is atomic number and s is a screening constant. Boding atomic radius one-half of the distance between covalently bonded nuclei. Bonding radius - decreases left to right, but increases from top to bottom. Z effective - increases left to right, slightly increases down a column. Ionization energy - decreases down a column, increases across a period. Electron affinity - becomes more exothermic as you go from left to right across a period. S of an electron in shell n = Ionic size depends upon nuclear charge, number of electrons, the orbitals in which electrons reside.
