Electrons in Atoms - continued Chapter 5 5.1 Light and Quantized Energy 5.2 Quantum Theory and the Atom 5.3 Electron Configurations

Atomic Orbitals Describe the location of electrons Orbital = region of space Principle quantum # (n) = energy level n = 1, 2, 3, 4, 5 … with increasing distance from the nucleus Energy Sublevels = s, p, d, f (see p. 133-134) s sphere 1 orbital max 2 electrons p dumbbell 3 (x, y, z) 6 d clover leaf 5 10 f 7 14 Max 2 electrons in each orbital

Order of filling orbitals (p.135)

Pauli Exclusion Principle: Hund’s Rule: Aufbau Principle: Electrons enter orbitals of lowest energy first Pauli Exclusion Principle: Atomic orbital can have at most 2 electrons Hund’s Rule: For orbitals of equal energy, 1 electron enters each orbital until all orbitals have 1 electron with parallel spins

Electron Configuration and Orbital Notation Si Ni Ar B Cr and Cu (exceptions) Al, Ge, Sb, Po

Link s, p, d, f orbitals to blocks in periodic table Noble gas shorthand notation for electron configuration Valence electrons = number of electrons in the highest energy level Electron dot (Lewis) structure http://www.youtube.com/watch?v=Vb6kAxwSWgU&feature=player_embedded