Chemistry 1301A/B Chapter Notes - Chapter 1: Effective Nuclear Charge, Ionic Radius, Valence Electron
Document Summary
1. 2 the periodic table and periodic trends s-block (group 1 and 2): either have 1 valance electron (group 1: alkali metals) or 2 valence electrons (group 2: alkaline earth metals). Group 1 have ns1 and group 2 has ns2 p-block (groups 13-18): 1(cid:1007) has (cid:1007) ve, 1(cid:1008) has (cid:1008) ve, 1(cid:1009) has (cid:1009) ve . Transition elements: groups 3-12 are known as the d-block elements. This block is 10 groups wide because the 5d-orbitals hold a maximum of 10 electrons. Periodic trends: the effective nuclear charge is defined as z* = z (# protons) ncore (# core electrons). It is the net positive charge experienced by the valence electrons when they are shielded by the core electrons from the full charge of the nucleus. From left to right, things get smaller because there are more protons, therefore more electrons being held more tightly because of the z*.