1. Hydrocarbon Compounds Functional Groups
Organic Chemistry
Hydrocarbon Compounds
Functional Groups

2. Organic Chemistry Involves Carbon
Carbon atoms form bonds with other atoms and also with other carbon atoms to form RINGS OR LONG CHAIN MOLECULES
Living things contain many carbon compounds

3. Characteristics of Organic Compounds
All have covalent bonds
Generally nonpolar molecules
Therefore, many are soluble in nonpolar solvents
not water “like dissolves like” (ex: Gasoline)
Have LOW MELTING POINTS/HIGH VAPOR PRESSURES
Held together by weak intermolecular forces
Have you ever seen or heard of “solid” gasoline?
Most are nonelectrolytes because they do not form ions

4. Hydrocarbons
Homologous Series of Hydrocarbons - similar properties and related structures
Alkanes, -enes & -ynes: Contain any number of carbon atoms, one after the other, in a long straight chain (table Q)
As the chain gets longer (i.e. MORE CARBON ATOMS)
-molecular size INCREASES (duh!)
-Intermolecular forces between molecules INCREASES – Vander Waals force increases and the molecules start to intertwine (wrap together)
Since intermolecular forces increase then Boiling points INCREASE while Freezing points Decrease (just like solutions)
Prefixes tell you how many carbon atoms are in the chain (table P)
Ethane C2H6
Ethene C2H4
Ethyne C2H2

5. Saturated and Unsaturated Compounds
Hydrocarbon Compounds can be separated into Saturated & Unsaturated compounds
Saturated: All carbon-to-carbon bonds are single
-Unsaturated: At least one of the carbon-to-carbon bonds is a double or triple bond
Are the following compounds Saturated or Unsaturated?
- Saturated
- Unsaturated
Unsaturated 
Saturated 

6. Butter – is a mixture of triglycerides of several different fatty acids

7. Naming the Hydrocarbons
Follows IUPAC naming system: (International Union of Pure & Applied Chemistry):
Need to identify where double & triple bonds are located in the chain by assigning a number
Rules for naming (page 702 in textbook): –
Find the longest Carbon Chain
Number the Carbons in the chain so that the lowest # possible is associated with the double or triple bond (NOTE: LOOK both “Left to Right” Direction & “Right to Left” Direction)
Select Prefix from Table P based on the longest chain carbon
Combine carbon prefix with either –ane, -ene or yne ending based upon carbon to carbon bonds
Give position number to double bond or triple bond
Combine name with # carbon followed by “-” and then Hydrocarbon name
1-butene
2-butene

8. Isomers
Compounds that have the SAME molecular formula (same atoms in the same molar ratio) but DIFFERENT structural formulas are called isomers
different compounds with different names and different physical properties such as boiling and melting point
Example: CH3OCH3 and C2H5OH OR
Pentane
Methyl Butane

9. Methyl (-CH3) Groups Methyl propane Butane Pentane Methyl Butane
If more than 1 methyl group, use di for 2, tri for 3, etc. in front of the Homologous Series Name
Methyl propane
Methyl Group
Butane
Pentane
Methyl Butane
Methyl Group

10. Di, Tri, … What is the longest continuous chain of carbons here?
(3 Carbons) so Propane
Any Methyl?
How Many Methyl Groups?
Therefore Name is:
Dimethyl Propane

11. Functional Groups TABLE R – Organic Functional Groups
Some organic compounds have one or more hydrogen atoms replaced by a particular arrangement of atoms known as a functional group
TABLE R – Organic Functional Groups
The symbol R, R’ & R” are used to represent any carbon chain
Ethanol
(R-OH)
R in this case is:

13. Names of Functional Groups
See Example column on Table R & note the ENDING
Carbon in the chain is numbered so carbon with –the functional group attached has lowest possible number
2-butanol
ethanol
If more than one functional group - then prefixes di, tri, tetra ,etc. are added (usually for Halides) Cl Cl
1,2-dichlorobutane

14. Organic Reactions
Organic reactions tend to proceed at a much slower rate than inorganic reactions.
Organic compounds undergo several reactions where usually only the functional group is involved
The larger part of the reacting molecule often remains unchanged during the reaction

15. Substitution Reactions
Replacing one atom or group of atoms with a different one (similar to Double Replacement)
Only saturated hydrocarbons or alkanes
An alkane (all single C-C bonds), a halogen replaces a hydrogen atom to produce a halocarbon
+ Br2 
+ HBr
hydrogen
bromide
ethane
bromine
bromoethane

16. Addition (If hydrogen is added it’s called hydrogenation)
Similar to a SYNTHESIS reaction
Limited to alkenes & alkynes (unsaturated hydrocarbons)
Involves breaking apart the double or triple bond and adding two or more atoms to carbon atoms
Characterized by the formation of a single product
ethene
bromine
1,2-dibromoethane

17. Fermentation enzyme C6H12O6  2 C2H5OH + 2 CO2
can occur in living systems
enzymes acts as catalysts to break down organic molecules
enzyme
C6H12O  C2H5OH CO2
glucose ethanol carbon dioxide

18. ALCOHOL + ACID ------ ESTER + WATER
Esterification
An alcohol and an acid form an ESTER and water
Esters have 2 names – the first name is derived from the alcohol name with a –yl ending. The second name comes from the organic acid with a –ate ending
Esters are responsible for the aromas associated with fruits, flowers and leaves
ALCOHOL ACID  ESTER + WATER + 
+ H2O
Methyl
ethanoate
water
methanol
ethanoic acid

19. Saponification Making of organic salts or “SOAP”
Hydrolysis (break down) of fats by bases
Soaps have both a polar end and a non-polar end
Therefore they can bring polar (water) and non-polar (grease) solutes together
The reason why a soapy sponge will clean a greasy countertop, but just water will not

20. Ester (fat) + NaOH → SOAP + glycerol

21. Polymerization
Polymers are molecules composed of repeating units – “PLASTICS”
Very, Very, Very long chains of carbons all bonded in a chain
Smaller hydrocarbon molecules combine to form very long and large molecules
Ex. Sodium polyacrylate
Occurs in nature in the production of proteins and starches

22. Sodium Polyacrylate