Electron Configurations 2

3. Electronic Configuration according to Quantum Mechanics The location of an electron is described by 3 terms. 1 st Term: Shell ( n ) n = 1 n = 2 n = 3 lone electron of Hydrogen

5. 2 nd Term: subshell - designated by s, p,d,f 1 s n = 2 n = 3 The first shell ( 1 ) has one subshell ( s ).

6. 2 nd Term: subshell - designated by s, p,d,f - refers to the shape(s) of the area in which the electron can be located. - also designates an energy level within the shell. 1 s n = 2 n = 3 The first shell ( 1 ) has one subshell ( s ). The s subshell is s pherical in shape and has 1 orbital 3rd Term: orbital

7. 2 nd Term: subshell - designated by s, p,d,f - refers to the shape(s) of the area in which the electron can be located. - also designates an energy level within the shell. 1 s n = 2 n = 3 The first shell ( 1 ) has one subshell ( s ). The s subshell is s pherical in shape and has 1 orbital 3rd Term: orbital Each orbital can accommodate 2 electrons

8. The Electronic Configuration of Hydrogen 1 s The first shell ( 1 ) has one subshell ( s ). The s subshell is s pherical in shape and has 1 orbital H 1 s 1 shell subshell # of electrons present energy H 1 s  Electronic configuration Orbital Energy Level Diagram

9. The Electronic Configuration of Helium He: Atomic # of 2, 2 electrons in a neutral He atom 1 s

10. The Electronic Configuration of Helium He: Atomic # of 2, 2 electrons in a neutral He atom H 1 s 1 He 1 s 2 He 1 s  1 s **if there are 2 electrons in the same orbital they must have the opposite spin. (Pauli’s Exclusion Principle)

12. 1 s The Electronic Configuration of Lithium (Li) Li: Z =3 Li has 3 electrons. 2 nd shell (2)

13. 1 s The Electronic Configuration of Lithium (Li) Li: Z =3 Li has 3 electrons. 2 nd shell - The 2nd shell ( n = 2 ) has 2 subshells which are s and p . 2 s 2 p

14. 1 s The Electronic Configuration of Lithium (Li) Li: Z =3 Li has 3 electrons. 2 nd shell 2 s 2 p Li 1 s 2 2 s 1 2 s  Li 1 s  Electronic configuration Orbital Energy Level Diagram

15. 1 s The Electronic Configuration of Berylium (Be) Be: Z =4 Be has 4 electrons. 2 nd shell 2 s 2 p Be 1 s 2 2 s 2 2 s  Be 1 s  Electronic configuration Orbital Energy Level Diagram 

17. subshell - designated by s, p,d,f - refers to the shape(s) of the area in which the electron can be located. - also designates an energy level within the shell. - relative energy: s < p < d < f s subshell: s pherical 1 orbital p subshell: p air of lobes x y z x y z

18. Our Orbital Picture of Be The first shell ( 1 s ) is filled. The 2 s orbital has 2 e - present. The 2 p orbitals are empty. The 2 p orbitals have room for 6 e -

20. 1 s The Electronic Configuration of Boron (B) B: Z =5 B has 5 electrons. 2 nd shell 2 s 2 p 1 s 2 nd shell 2 s 2 p Be 1 s 2 2 s 2 2 s  Be 1 s  B 1 s 2 2 s 2 2 p 1 2 p  2 s  B 1 s 

22. 1 s The Electronic Configuration of Carbon (C) C: Z =6 C has 6 electrons. 2 nd shell 2 s 2 p 1 s 2 nd shell 2 s 2 p B 1 s 2 2 s 2 2 p 1 2 p  2 s  B 1 s  C 1 s 2 2 s 2 2 p x 1 p y 1 2 p   2 s  C 1 s 

23. Our Orbital Picture of C The first shell ( 1 s ) is filled. The 2 s orbital has 2 e - present. 2 2 p orbitals have 1 e - each.

25. d subshell: double dumbells xy z 2 xz x y yz x 2- y 2

28. Atomic Radii within a Group Lithium (Z=3); n = 2 Sodium (Z=11); n = 3 Hydrogen (Z=1); Shell (n)=1 + + + e - 2e - 8e - 2e - + + + + e - + e -

29. Lithium (Z=3) n = 2 Beryllium (Z=4) n = 2 Boron (Z=5) n = 2 If protons were light bulbs….and electrons were moths…... + + + e - 2e - + + + e - 2e - e - + + + + e - 2e - e - e - + + B e - e - e - Be e - e - Li e - + + + e - 2e - + + + e - 2e - e - +

30. Lithium (Z=3) Beryllium (Z=4) Boron (Z=5)  Increasing  Increasing + + + e - 2e - + + + e - 2e - e - + + + + e - 2e - e - e - + +

32. H. Chemistry OBE 2/16/11 Of the elements Mg, Cl, Na, and P which would have the largest atomic radius? Explain this in terms of trends in the periodic table (periodicity). + + + e - 2e - + + + e - 2e - e - + + + + e - 2e - e - e - + +

33. First Ionization Energy Lithium (Z=3) Sodium (Z=11) Hydrogen (Z=1) + e - + + + e - 8e - 2e - + + + + e - + e - H + + + + e - 2e - Li + e - 8e - 2e - + + + + Na +

34. First Ionization Energy e - Lithium (Z=3) 8e - Sodium (Z=11) 2e - 2e - e - Hydrogen (Z=1) e -  Decreasing + + + + + + + +

35. Lithium (Z=3) 3 protons screened by 2 e - e - 2e - Beryllium (Z=4) 4 protons screened by 2 e - Boron (Z=5) 5 protons screened by 2 e - e - 2e - e - e - 2e - e - e - 1 e - removed = 2s 0 1 e - removed = 2s 1 1 e - removed = 2s 2 2p 0 + + + + + + + + + + + +  Decreasing  Decreasing

36. Lithium (Z=3) 3 protons screened by 2 e - e - 2e - Beryllium (Z=4) 4 protons screened by 2 e - Boron (Z=5) 5 protons screened by 2 e - e - 2e - e -  Decreasing  Decreasing + + + + + + + + + + e - 2e - e - e - + +

37.  Increasing  Increasing Trends in the Periodic Table Atomic Radii (Size) First Ionization Energy  Decreasing  Decreasing

38. Electron Affinity e - Fluorine (Z=9) 8e - Chlorine (Z=17) 2e - 2e - 7e - 7e - 2e - 8e - F - e - 8e - 2e - 8e - Cl - + + + + + + + + + + + + + +

39. Trends in the Periodic Table First Ionization Energy  Decreasing  Decreasing  Decreasing  Decreasing Electron Affinity

40. Predicting Stable Ions 8e - Sodium (Z=11) 2e - e - e - 8e - 2e - Na + 8e - Chlorine (Z=17) 2e - 7e - e - 8e - 2e - 8e - Cl - + + + + + + + + + + + + + + + +