3. What are the building blocks?  Carbon  Hydrogen  Oxygen  Nitrogen  Phosphorus  Chlorine Atoms  Methane  Formaldehyde  Hydrogen cyanide  Phosphorus pentachloride Molecules Subatomic particles  Protons  Electrons s orbital p orbital d orbital Hybrids

6. The forces at work are: Electromagnetic: Repulsion of like charges: proton-proton and electron-electron Attraction of unlike charges: proton-electron. Magnetic: Electron spin introduces magnetic forces. Electrons with opposite spins produce opposite magnetic poles. Opposite magnetic poles attract. Opposite spin is required for electrons to occupy the same orbital.

7. The Energies involved: Electron (orbital) Potential Energy: 2s 2p 3s 3p 3d 4s 4p 1s ENERGY LEVEL

8. 120 o 109.5 o 90 o 180 o Bond Angles

9. PxPx PyPy PzPz PxPx PyPy PzPz

10. Methane building blocks

12. 2s2p x 2p z 2p y 1s sp 3 sp 3 109.5 o Promote Hybridize x z y Methane: Carbon

13. CH 2 O 120 o

14. 2s2p x 2p z 2p y 1s sp 2 sp 2 sp 2 120 o Hybridized Formaldehyde: Carbon Promoted 120 o Trigonal Planar 2s + 2p x + 2p z

15. 2s2p x 2p z 2p y 1s sp 2 sp 2 sp 2 120 o Hybridized Formaldehyde: Oxygen 120 o Trigonal Planar Lone Pairs 2s + 2p x + 2p z

16. Formaldehyde Sigma bond  bond

18. 2s2p x 2p z 2p y 1s sp Promoted Hybridized Hydrogen Cyanide: Carbon 2s + 2p x Linear

19. 2s2p x 2p z 2p y 1s sp Hybridized Hydrogen Cyanide: Nitrogen 2s + 2p x Linear

20.  bond

21. PCl 5

22. 3s3p x 3p z 3p y 2 Neon 120 o Hybridized Phosphorus Pentachloride: Phosphorus Trigonal Bipyrimidal sp 3 d sp 3 d sp 3 d sp 3 d sp 3 d d xz d yz d xy d x 2 -y 2 d z 2 120 o 90 o Promoted