Orbitals and Shells ■ Orbitals are organized into shells of increasing size and energy ■ Different shells contain different numbers and kinds of orbitals Each orbital can be occupied by two electrons First shell contains one s orbital,denoted 1s ■ Second shell contains one s orbital(2s)and three p orbitals(2p) Third shell contains an s orbital(3s),three p orbitals (3p),and five d orbitals (3d) Orbitals and Shells „ Orbitals are organized into shells of increasing size and energy „ Different shells contain different numbers and kinds of orbitals „ Each orbital can be occupied by two electrons „ First shell contains one s orbital, denoted 1 s „ Second shell contains one s orbital ( 2 s) and three p orbitals ( 2 p ) „ Third shell contains an s orbital ( 3 s), three p orbitals ( 3 p), and five d orbitals (3 d )