1. Organic Reactions
- Hydrocarbons -

2. Flow Chart of Organic Reactions

3. Reactions of Alkanes
Single covalent bonds between carbon atoms are relatively difficult to break, and thus alkanes are rather unreactive
TWO Common Reactions of Alkanes
Combustion
Substitution

4. 1) Combustion Reactions
∆ hydrocarbon + oxygen  carbon dioxide and water
C3H8(g) +
5O2(g) 
3CO2(g) +
4H2O(g)
NOTE: Assume COMPLETE combustion
unless otherwise stated

5. Flow Chart of Organic Reactions

6. 2) Substitution Reaction
C-C bonds are difficult to break, H atom may be “substituted” by a halogen atom using F2, Cl2, and Br2
Reactions with F2 are fast, Cl2 and Br2 require heat or UV to dissociate the halogen molecule first
Products  halogenated alkanes  called alkyl halides

7. Substitution reaction between ethane & bromine

8. As reactions proceeds, bromoethane concentration increases resulting in more substitution reactions

9. Reactions of Alkenes & Alkynes
Due to double or triple bonds alkenes and alkynes are more reactive than alkanes
Traditionally alkenes and alkynes undergo ADDITION reactions – where atoms are added to the molecule without losing hydrogen atoms

10. Reactions of Alkenes & Alkynes
Four Common Addition Reactions
Halogenation (with Br2 and Cl2)
Hydrogenation (with H2)
Hydrohalogenation (with hydrogen halides)
Hyration (with H2O)

12. Flow Chart of Organic Reactions

14. Flow Chart of Organic Reactions

16. Flow Chart of Organic Reactions

18. Markovnikov’s Rule

19. “the rich get richer” Markovnikov’s Rule
When a hydrogen halide or water is added to an alkene or alkyne, the hydrogen atom bonds to the carbon atom within the double bond that already has more hydrogen atoms.
“the rich get richer”

20. Learning Checkpoint
Assigned Questions:
p. 27 Practice UC # 1, 2, 3

21. Reactions of Aromatic Hydrocarbons
Generally, do NOT undergo addition reactions
Less reactive than alkenes
Aromatic hydrocarbons undergo substitution reactions (easier than alkanes)
Reactivity of aromatic hydrocarbons between alkanes and alkenes

27. Learning Checkpoint Assigned Questions: p. 30 Practice UC # 4, 5, 6
p. 31 Section 1.3 UC # 2, 3, 4