1. Organic Chemistry
Introduction

2. Organic Chemistry
 - is the study of compounds that contain
carbon.
There are lots of them.
90% + of known compounds are Organic
Why?
Because carbon forms chains

3. Hydrocarbons
Organic compounds that contain only
hydrogen and carbon.

4. Alkanes
Hydrocarbons containing only single
covalent bonds
Ex: CH4 – methane – natural gas
Dot diagram
Dashes

5. Reminders about dot diagrams
Only show 2 D shape
Carbon likes to bond in ____ places
Hydrogen likes to bond in ____ place

6. Dot diagram for C2H6

7. Straight-chain alkanes
Contain any number of C atoms, one after
the other, in a chain.
You should know the names of these next
alkanes

8. First 10 straight-chained alkanes
Methane CH4 CH4
Ethane C2H6 CH3CH3
Propane C3H8 CH3CH2CH3
Butane C4H10 CH3CH2CH2CH3
Pentane C5H12 CH3CH2CH2CH2CH3
Hexane C6H14 CH3CH2CH2CH2CH2CH3
Heptane C7H16 CH3CH2CH2CH2CH2CH2CH3
Octane C8H18 CH3CH2CH2CH2CH2CH2CH2CH3
Nonane C9H20 CH3CH2CH2CH2CH2CH2CH2CH2CH3
Decane C10H22 CH3CH2CH2CH2CH2CH2CH2CH2CH2CH3

9. Homologous series
A group of compounds in which there is a
constant increment of change in molecular
structure from one compound in the series
to the next.
The alkanes differ by one CH2 group each
time
CnH2n+2

10. Types of formulas
Molecular formula – C4H10
Complete structural formula
Condensed structural formula – C – H
bonds are understood.
Condensed structural formula – C-H and
C-C bonds understood
Carbon skeleton; hydrogens understood

11. Draw a complete structural formula for the
straight-chained alkane having 3 carbons

12. Branched-chain Alkanes
Substituent – an atom or group of atoms
that can take the place of a hydrogen atom
on a parent hydrocarbon molecule.
Parent chain – the longest carbon chain.
May not always be written in a straight line on
paper.

15. Alkyl group – a hydrocarbon substituent
CH3 – methyl
CH3CH2 – ethyl
CH3CH2CH2 – propyl
Alkyl group = alkane – 1 H
Name = -ane + yl
What would CH3CH2CH2 CH2be called?

16. Branched-chain alkane
An alkane with one or more alkyl groups
attached.

17. Naming a branched-chain alkane
1. Find the longest chain of carbons. This
is the parent chain
2. # the carbons on the parent chain.
Starting with the end that will give the
substituents the smallest numbers
3. Add #s to the names of the substituent
groups to identify their positions on the
chain.

18.  4. Use prefixes to indicate if a group appears
more than once.
Di – 2
Tri – 3
Tetra – 4
Penta – 5
 5. List the names of the alkyl substituents in
alphabetical order (ignore prefixes when
alphabetizing.)
 6. Use proper punctuation
Commas separate #s from #s
Hyphens separate #s from words

21. Properties of alkanes
Nonpolar – electrons are shared about
equally
Very weak van der Walls forces
(dispersion)
Have a low mass, low boiling point
Do not dissolve in water.
Flammable