2. What is organic chemistry?
• study of carbon, the compounds it makes, and
the reactions it undergoes
• over 16 million carbon-containing compounds
are known
• because the C-C single bond (348 kJ mol-1) and
the C-H bond (412 kJ mol-1) are strong, carbon
compounds are stable
• carbon can form chains and rings
3. Homologous series/compounds (10.1.1)
• related compounds that have the same
functional group (groups of atoms found within
molecules that are involved in the chemical reactions
characteristic of those molecules)
4.
5. • differ from each other by a CH2 unit
• can be represented by a general formula
– examples:
• CnH2n+2 (alkanes) or CnH2n (alkenes) or…
6.
7. • have similar chemical properties
• have physical properties that vary in a
regular manner as the number of
carbon atoms increases
– Example: the alkanes
8.
9. Trends in boiling points of members of a
homologous series (10.1.2)
• melting point and
boiling point increase
with more carbon
atoms
• Why?
– intermolecular
forces increase
– adding a CH2 adds
more electrons
• this increases the Van
der Waal’s forces
Alkane Formula Boiling
Pt./oC
methane CH4 -162.0
ethane C2H6 -88.6
propane C3H8 -42.2
butane C4H10 -0.5
12. • empirical formula
– simplest ratio of
atoms in a
molecule
• molecular formula
– actual numbers
of atoms in a
molecule
Empirical
Formula
Molecular
Formula
CH4 CH4
CH3 C2H6
CH2O C6H12O6
CH2 C4H8
CH2 C8H16
13. structural formula
• unambiguously shows how the atoms are
bonded together
• can use condensed structural formulas
– bonds are omitted, repeated groups put
together, side chains put in brackets
• CH3CH2CH2CH2CH2CH3
–or even CH3(CH2)4CH3
• CH3CH(CH3)CH3
19. • hydrocarbon chains where all the bonds between
carbons are SINGLE bonds
• CnH2n+2
• draw out and write the structural formulas for
all isomers that can be formed by:
– CH4
– C2H6
– C3H8
– C4H10
– C5H12
– C6H14
Richard Thornley 10.1.5
2:54
Structural formulas for the isomers of non-
cyclic alkanes up to C6 (10.1.5)
Alkanes
20. 1. Richard Thornley 3:35
2. Determine the longest carbon chain
– Use the prefix to denote the number carbons
Naming the isomers (IUPAC) of non-cyclic
alkanes up to C6 (10.1.6)
1 Meth-
2 Eth-
3 Prop-
4 But-
5 Pent-
6 Hex-
Monkeys
Eat
Peeled
Bananas
21. 3. use the suffix “-ane” to indicate that the substance
is an alkane
4. number the carbons in the chain consecutively,
starting at the end closest to a substituent
(groups attached to the main chain/most busy
end)
22. 5. name and number the location of each
substituent
– the name of the substituent will be written before the main
chain and will end with “–yl” (or just memorize the below)
• CH3 is methyl
• C2H5 is ethyl
• C3H7 is propyl
And with 2 or more side chains:
5. use prefixes di-, tri-, tetra-, to indicate when
there are multiple side chains of the same type
6. use commas to separate numbers and hyphens
to separate numbers or letters.
7. name the side chains in alphabetical order
23. • How about C5H12? The isomers are:
Pentane 2-methyl-butane 2,2-dimethyl propane
24. Nomenclature Practice
C
H3 CH3
CH3
C
H3
Cl
Name this compound
Step #1: For a branched hydrocarbon, the longest
continuous chain of carbon atoms gives the root name
for the hydrocarbon
1
5
2 4
3
9
6
8
7
9 carbons = nonane
25. Nomenclature Practice
Name this compound
C
H3 CH3
CH3
C
H3
Cl
1
5
2 4
3
9
6
8
7
9 carbons = nonane
Step #2: When alkane groups appear as substituents, they are named
by dropping the -ane and adding -yl.
CH3 = methyl
chlorine = chloro
26. Nomenclature Practice
Name this compound
C
H3 CH3
CH3
C
H3
Cl
1
5
2 4
3
9
6
8
7
9 carbons = nonane
CH3 = methyl
chlorine = chloro
Step #3: The positions of substituent groups are
specified by numbering the longest chain of carbon
atoms sequentially, starting at the end closest to the
branching.
1 9 NOT 9 1
27. Nomenclature Practice
Name this compound
C
H3 CH3
CH3
C
H3
Cl
1
5
2 4
3
9
6
8
7
9 carbons = nonane
CH3 = methyl
chlorine = chloro
Step #4: The location and name of each substituent are
followed by the root alkane name. The substituents are
listed in alphabetical order (irrespective of any prefix),
and the prefixes di-, tri-, etc. are used to indicate
multiple identical substituents.
2-chloro-3,6-dimethylnonane
28. Structural formulas for the isomers of the straight
chain alkenes up to C6 (10.1.7)
• alkenes have a double bond between two or more of
the carbons
• CnH2n
• draw out and write the structural formulas for all isomers
that can be formed by each
– C2H4
– C3H6
– C4H8
– C5H10
– C6H12
Alkenes
Richard Thornley 10.1.7 (1:37)
29. 1. suffix changes to “-ene”
2. when there are 4 or more carbon atoms in a
chain, the location of the double bond is
indicated by a number
3. begin counting the carbons closest to the
end with the C=C bond
– numbering the location of the double
bond(s) takes precedence over the location
of any substituents
1-butene 2-butene
but-1-ene but-2-ene
Naming the isomers (IUPAC) of straight chain
alkenes up to C6 (10.1.8)
