1. 2-Methyl-Cis-2-trans-4-hexadiene
Warm-up
2-Methyl-Cis-2-trans-4-hexadiene
Draw in kekule
Draw in Bow-tie

2. Rx of unsaturated HC

3. Reactions of Alkenes and Alkynes
Double/triple bond are unstable
they make alkenes/alkynes very reactive.
Two classes of Rx:
Addition Rx: double bonds break open allowing addition of new elements to alkane
Polymerization Rx: double bonds break open connecting monomers

4. Four types of Addition Rx
Hydrogenation –addition of H2
Hydration –addition of H2O
Halogenation – addition of F, Cl, Br, I
Acid hydration – addition of a HCl, H2SO4

5. Hydrogenation Rx Breaking a double bond in presence of H2-gas
Alkene becomes Alkane

6. Hydration Rx
Breaking a double bond by inserting H2O in form of –OH and H
Manufacturing of industrial Alcohols
Ethene Ethanol

7. Halogenation Rx Breaking the double bond with Halogen gasses
Production of Haloalkanes

8. Acid Hydration Rx
Acid (HCl) breaks into H+ and Cl- which are added to the new open bond
Another way of producing Haloalkanes
CH2 =CH2 + HCl H Cl
H C C H
H H

9. Polymerization
connecting small monomers to large polymers using distinct Rx
Natural polymers: cellulose, starch, proteins, DNA
Polymerizing Rx is a Dehydration Rx: a reaction that splits out water (opposite of hydration)

10. Synthetic Polymerization
Polymerization Rx: breaking double bonds to connect monomers
Use of small alkene monomers
Name of polymer: “Poly”alkenename

11. Blowmolding
plastic bottle manufacturing

12. PE-Polyethylene

13. Polyvinylchloride-PVC
Hard, very stable plastic
Problem: leaks Cl2 or HCL gas when combusted or when it corrodes

14. Styrofoam
Polystyrene

15. Oh yes….alkenes, -ynes combust too
Write the balanced combustion of
Propane
Propene
Propyne

16. Warm-up
Ethene is a gas and Polyethene (= polyethylene) is the clear solid plastic bottles are made out of. What causes this phase change? Write a paragraph….