Energy Level Diagram for Hydrogen (n=4, n=3, n=2, n=1)

6. Energy Level Diagram for Hydrogen n = 4 n = 3 n = 2 n = 1 4p 4p 3p 3p 3p 2p 2p 4f 4s 3s 2s 1s 2p 3d 4f 3d 3d 4f 4f 4f 4f 3d 4f 4d 4d 4d 4d 4d 3d 4p Each energy level of the hydrogen atom has a certain number of orbitals available for electrons

7. Energy levels are designated by a quantum number called “n – the principal quantum number” Level n=1 has just the 1s orbital

8. Energy Level Diagram for Hydrogen n = 4 n = 3 n = 2 n = 1 4p 4p 3p 3p 3p 2p 2p 4f 4s 3s 2s 1s 2p 3d 4f 3d 3d 4f 4f 4f 4f 3d 4f 4d 4d 4d 4d 4d 3d 4p The n=2 level has 4 orbitals, a 2s (same shape but larger than a 1s) and three 2p orbitals

9. Energy Level Diagram for Hydrogen n = 4 n = 3 n = 2 n = 1 4p 4p 3p 3p 3p 2p 2p 4f 4s 3s 2s 1s 2p 3d 4f 3d 3d 4f 4f 4f 4f 3d 4f 4d 4d 4d 4d 4d 3d 4p N=3 level has one 3s, three 3p orbitals and five 3d orbitals. Each level “n” has n2 orbitals

10. Energy Level Diagram for Hydrogen n = 4 n = 3 n = 2 n = 1 4p 4p 3p 3p 3p 2p 2p 4f 4s 3s 2s 1s 2p 3d 4f 3d 3d 4f 4f 4f 4f 3d 4f 4d 4d 4d 4d 4d 3d 4p Level n = 4 has a 4s, three 4p orbitals, five 4d orbitals and seven 4f orbitals

11. 3d 4f 2p 3p 3p 2p 2p 3s 4s 4p 2s 1s 4f 3p 4p 4f 4p 4f 4f 4f 4f 4d 4d 4d 4d 3d 3d 3d 3d 4d Energy Level Diagram for Hydrogen n = 4 n = 3 Energy In a hydrogen atom, all the sublevels of each energy level “n” have the same energy. Eg 2p’s are at the same energy as 2s’s3s’s, 3p’s and 3d’s all have the same energy etc… n = 2 n = 1

12. In “multi-electron” atoms (atoms other than hydrogen), the “sublevels” have different energies. E.g. the 2p orbitals have slightly higher energy than the 2s. The 3p’s are higher than the 3s and the 3d’s are higher still.

16. Drawing a Bohr Diagram To draw Bohr Diagrams: 1. Find the PEN of the atom or ion 2. Draw the nucleus as the symbol of the element. 3. Place the number of electrons in orbits around the nucleus by drawing circles around the nucleus. 1st shell – 2 e-  as per the energy level diagram 2nd shell – 8 e- 3rd shell – 8 e- 4th shell – 18 e-

21. YOU WILL NOT HAVE THIS FOR EXAMS!

23. Practice Time • Predict the electronic configuration of the following: • Si • Tc • Ca • Zr • Ga

26. Examples • Al: [Ne] 3s2 3p1 You try for... • Zr • Ga • Co