1. Models of the Atom

2.  An atomic orbital is a region of space where an electron can be found  There are energy levels existing outside the nucleus ◦ These levels correspond to the periods of the periodic table  Each energy sublevel corresponds to orbitals within a particular energy level

3.  Each sublevel corresponds to a different shape ◦ s, p, d, f ◦ Orientations of sublevels are referred to as orbitals  The s sublevel is a sphere and can only have one orientation in space  The p sublevel is dumb-bell shaped and can have three orientations in space  The d sublevel has clover-leaf shapes and has five orientations  The f sublevel is complex and can have seven orientations

4.  Each orientation (orbital) of a sublevel can have a maximum of two electrons  This means that: ◦ The s sublevel can house a maximum of 2 e- ◦ 3 orientations of p = 6e- ◦ 5 orientations of d = 10e- ◦ 7 orientations of f = 14e- ◦ The principal quantum number corresponds to the number of sublevels that can exist for that element

5.  First energy level can only have one sublevel (s) = 2e-  Second energy level can have two sublevels (s, p) = 10e-  Third energy level can have three sublevels (s, p, d) = 18e-  Fourth energy level can have four sublevels (s, p, d, f) = 32e-