1.  Bohr model was 1 dimensional  Scientist started thinking about electrons in the forms of waves and particles  DeBrogile Equation  Schroedinger Equation  Heisenberg Uncertainty Principle  Narrows down location even more than electron configuration QUANTUM NUMBERS

2.  Principle quantum number (n) = Energy level  Describes the size of orbital  Always a + whole number  Never zero QUANTUM NUMBERS

3.  Angular quantum number (l) = sublevel  Describes the shape of the orbitals  Always a whole number  Ranges from 0 to n-1  L = 0 = s = sphere  L = 1 = p = dumbbell  L = 2 = d = clover leaf  L = 3 = f = complex shapes QUANTUM NUMBERS

4.  Magnetic quantum number (m or m l ) = orbital  Describes orientation of orbital  Always a whole number  Ranges from –L…L QUANTUM NUMBERS

5.  Spin quantum number (s or m s )  Used to distinguish 2 electrons in each lobe of orbital  Can only be +½ or -½  Pauli Exclusion Principle QUANTUM NUMBERS

6.  n = principle = size  The coefficient in e- configuration  1s 2 n= 1  3d 10 n = 3  l = angular = shape  SL = 0  PL = 1  DL = 2  FL = 3  m = magnetic = orientation  Values range from -L…0…+L  s (m s ) = spin  Up arrow = +1/2  Down arrow = - 1/2 QUANTUM NUMBERS

7.  Each electron has its own unique set of quantum numbers  Helpful to draw out the spin diagram  Determine the quantum numbers for electrons in oxygen: ______ ______ ______ ______ ______ QUANTUM NUMBERS

8.  Some helpful short cuts…  Number of orbitals in an energy level= n 2  How many orbitals are contained in the 3 rd energy level?  3 rd energy level and below?  Maximum number of electrons in energy level = 2n 2  What is the maximum number of electrons in the 2 nd energy level? QUANTUM NUMBERS

9. WRITE 4 QUANTUM NUMBERS FOR EACH ELECTRON IN A HYDROGEN ATOM E- #NLMLML MsMs