1. Objectives SWBAT Define an organic compound.
Explain how the structure and bonding of carbon lead to the diversity of organic compounds.
Distinguish among the structures of alkanes, alkenes, and alkynes.
Recognize characteristics of organic compounds such as alkanes.

2. Introduction to Organic Chemistry
Organic Compounds

3. Organic Compounds Organic compound:
Compound made from one or more C atoms with many H atoms.
May also contain O, S, N, and halogens.
Hydrocarbon = organic cpd with C & H.
Saturated = all single bonds
Unsaturated = multiple bonds

4. Properties of Organic Compounds
Have low melting points and boiling points.
Are flammable.
Are soluble in nonpolar solvents therefore are not soluble in water.
Oil (organic) and
water (inorganic)

5. Organic vs. Inorganic
Propane, C3H8, is an organic compound used as a fuel.
NaCl, salt, is an inorganic compound composed of Na+ and Cl− ions.
Why is propane an
organic compound, but
NaCl is not?

6. Why Carbon? (remember biology)
In carbon compounds
Carbon has 4 valence electrons and hydrogen has 1. •
• C • H •
To achieve an octet, C forms four covalent bonds.
H H
 
H  C  H H C H
H H CH4 , methane

7. Alkanes
Saturated hydrocarbon (only SINGLE bonds between adjacent carbon atoms).
Formula: CnH2n+2

8. Names of Alkanes The names of alkanes
Use a prefix to indicate the number of carbons in a chain.
End in –ane.

9. Prefixes for hydrocarbons

10. Structural Formulas for Alkanes
Alkanes are written with structural formulas that are
Expanded to show each bond.
Condensed to show each carbon atom and its attached hydrogen atoms.
Expanded Condensed H
H C H CH4 , methane
In methane, CH4 the four valence electrons of carbon are shared with the single electrons of four hydrogen (H) atoms. Each pair of electrons is a single bond, which can be drawn as a line. When a structure is drawn to show each bond, it is called a complete structural formula.

12. Learning Check A. Write the condensed structural formula for:
H H H H H
H C C C C C H
H H H H H
B. What is its molecular formula?
C. What is its name?

13. Learning Check Write the condensed structural formula for A. ethane
B. heptane

14. Alkyl groups Alkyl groups are Alkanes that are missing one H.
Side groups attached to carbon chains.
Named with a –yl ending. H
H C CH3 methyl
H H
H C C CH3 CH2 ethyl

15. Alkanes with Alkyl Groups
CH3
CH3 CH CH methylpropane
methyl groups
CH CH3
CH3 CH CH2 CH CH ,4-dimethylpentane

16. Guide to Naming All Alkanes
Give the name of CH3 CH3
 
CH3─CH─CH─CH3
STEP Longest chain is butane.
STEP Number chain. CH3 CH3
 
STEP 3 Locate alkyl groups and name.
2,3-dimethylbutane

17. Alkenes and Alkynes
Alkenes - unsaturated hydrocarbon with at least one double bond
CnH2n
Alkynes - unsaturated hydrocarbon with at least one triple bond.
CnH2n-2

18. Naming Alkenes and Alkynes
Use the same prefixes as you did for naming Alkanes.
Replace “ane” with “ene” or “yne”

19. Rules for Naming Hydrocarbons
Find the longest continuous chain of carbon atoms. Use the proper prefix to name the chain.
If it is an alkane add the ending –ane
If it is an alkene add the ending –ene
If it is an alkyne add the ending -yne
Number the carbon atoms in the chain so that the lowest possible numbers will be given for the attached side groups
Name the groups attached to the chain by adding a prefix –yl to the stem name. Locate them by identifying the number assigned to the carbon it is located on
If there is more than one group arrange them in alphabetical order

20. Halogen Substitution A hydrogen can be replaced with Chloro -Cl
Bromo -Br
Iodo -I
Name using the lowest number carbon